from: https://github.com/MarkLeith/mysql-sys/blob/master/README.md
mysql 5.7 提供 SYS Schema,从SYS database中，可以获取mem page、io 、latch/mutex/lock等各种性能数据，方便做peformance turning 和 troubleshooting。比如可以方便获取2个sql发生 lock block等信息。越来越像oracle了。
# The MySQL sys schema
A collection of views, functions and procedures to help MySQL administrators get insight in to MySQL Database usage.
There are install files available for 5.6 and 5.7 respectively. To load these, you must position yourself within the directory that you downloaded to, as these top level files SOURCE individual files that are shared across versions in most cases (though not all).
## Installation
The objects should all be created as the root user (but run with the privileges of the invoker).
For instance if you download to /tmp/mysql-sys/, and want to install the 5.6 version you should:
cd /tmp/mysql-sys/
mysql -u root -p < ./sys_56.sql
Or if you would like to log in to the client, and install the 5.7 version:
cd /tmp/mysql-sys/
mysql -u root -p
SOURCE ./sys_57.sql
Alternatively, you could just choose to load individual files based on your needs, but beware, certain objects have dependencies on other objects. You will need to ensure that these are also loaded.
### Generating a single SQL file
There is bash script within the root of the branch directory, called `generate_sql_file.sh`, that allows you to create a single SQL file from the branch.
This includes substitution parameters for the MySQL user to use, and whether to include or exclude `SET sql_log_bin` commands from the scripts. This is particularly useful for installations such as Amazon RDS, which do not have the root@localhost user, or disallow setting sql_log_bin.
When run, this outputs a file named such as `sys_<sys_version>_<mysql_version_identifier>_inline.sql`, i.e. `sys_1.2.0_56_inline.sql` is sys version 1.2.0, built for MySQL 5.6.
#### Options
* v: The version of MySQL to build the sys schema for, either '56' or '57'
* b: Whether to omit any lines that deal with sql_log_bin (useful for RDS)
* u: The user to set as the owner of the objects (useful for RDS)
* m: Whether to generate a mysql_install_db / mysqld --initialize formatted file
#### Examples
Generate a MySQL 5.7 SQL file that uses the 'mark'@'localhost' user:
./generate_sql_file.sh -v 57 -u "'mark'@'localhost'"
Generate a MySQL 5.6 SQL file for RDS:
./generate_sql_file.sh -v 56 -b -u CURRENT_USER
Generate a MySQL 5.7 bootstrap file:
./generate_sql_file.sh -v 57 -m
## Overview of objects
### Tables
#### sys_config
##### Description
Holds configuration options for the sys schema. This is a persistent table (using the `InnoDB` storage engine), with the configuration persisting across upgrades (new options are added with `INSERT IGNORE`).
The table also has two related triggers, which maintain the user that `INSERTs` or `UPDATEs` the configuration - `sys_config_insert_set_user` and `sys_config_update_set_user` respectively.
Its structure is as follows:
```SQL
+----------+--------------+------+-----+-------------------+-----------------------------+
| Field | Type | Null | Key | Default | Extra |
+----------+--------------+------+-----+-------------------+-----------------------------+
| variable | varchar(128) | NO | PRI | NULL | |
| value | varchar(128) | YES | | NULL | |
| set_time | timestamp | NO | | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
| set_by | varchar(128) | YES | | NULL | |
+----------+--------------+------+-----+-------------------+-----------------------------+
```
Note, when functions check for configuration options, they first check whether a similar named user variable exists with a value, and if this is not set then pull the configuration option from this table in to that named user variable. This is done for performance reasons (to not continually `SELECT` from the table), however this comes with the side effect that once inited, the values last with the session, somewhat like how session variables are inited from global variables. If the values within this table are changed, they will not take effect until the user logs in again.
##### Options included
| Variable | Default Value | Description |
| ------------------------------------ | ------------- | ------------------------------------------------------------------------------ |
| statement_truncate_len | 64 | Sets the size to truncate statements to, for the `format_statement()` function. |
| statement_performance_analyzer.limit | 100 | The maximum number of rows to include for the views that does not have a built-in limit (e.g. the 95th percentile view). If not set the limit is 100. |
| statement_performance_analyzer.view | NULL | Used together with the 'custom' view. If the value contains a space, it is considered a query, otherwise it must be an existing view querying the performance_schema.events_statements_summary_by_digest table. |
| diagnostics.allow_i_s_tables | OFF | Specifies whether it is allowed to do table scan queries on information_schema.TABLES for the `diagnostics` procedure. |
| diagnostics.include_raw | OFF | Set to 'ON' to include the raw data (e.g. the original output of "SELECT * FROM sys.metrics") for the `diagnostics` procedure.|
| ps_thread_trx_info.max_length | 65535 | Sets the maximum output length for JSON object output by the `ps_thread_trx_info()` function. |
### Views
Many of the views in the sys schema have both a command line user friendly format output, as well as tooling friendly versions of any view that contains formatted output duplicated as an x$ table.
The examples below show output for only the formatted views, and note where there is an x$ counterpart available.
#### host_summary / x$host_summary
##### Description
Summarizes statement activity, file IO and connections by host.
When the host found is NULL, it is assumed to be a "background" thread.
##### Structures (5.7)
```SQL
mysql> desc host_summary;
+------------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| statements | decimal(64,0) | YES | | NULL | |
| statement_latency | text | YES | | NULL | |
| statement_avg_latency | text | YES | | NULL | |
| table_scans | decimal(65,0) | YES | | NULL | |
| file_ios | decimal(64,0) | YES | | NULL | |
| file_io_latency | text | YES | | NULL | |
| current_connections | decimal(41,0) | YES | | NULL | |
| total_connections | decimal(41,0) | YES | | NULL | |
| unique_users | bigint(21) | NO | | 0 | |
| current_memory | text | YES | | NULL | |
| total_memory_allocated | text | YES | | NULL | |
+------------------------+---------------+------+-----+---------+-------+
12 rows in set (0.15 sec)
mysql> desc x$host_summary;
+------------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| statements | decimal(64,0) | YES | | NULL | |
| statement_latency | decimal(64,0) | YES | | NULL | |
| statement_avg_latency | decimal(65,4) | YES | | NULL | |
| table_scans | decimal(65,0) | YES | | NULL | |
| file_ios | decimal(64,0) | YES | | NULL | |
| file_io_latency | decimal(64,0) | YES | | NULL | |
| current_connections | decimal(41,0) | YES | | NULL | |
| total_connections | decimal(41,0) | YES | | NULL | |
| unique_users | bigint(21) | NO | | 0 | |
| current_memory | decimal(63,0) | YES | | NULL | |
| total_memory_allocated | decimal(64,0) | YES | | NULL | |
+------------------------+---------------+------+-----+---------+-------+
12 rows in set (0.00 sec)
```
##### Example
```SQL
mysql> select * from host_summary;
+------+------------+-------------------+-----------------------+-------------+----------+-----------------+---------------------+-------------------+--------------+
| host | statements | statement_latency | statement_avg_latency | table_scans | file_ios | file_io_latency | current_connections | total_connections | unique_users |
+------+------------+-------------------+-----------------------+-------------+----------+-----------------+---------------------+-------------------+--------------+
| hal1 | 2924 | 00:03:59.53 | 81.92 ms | 82 | 54702 | 55.61 s | 1 | 1 | 1 |
+------+------------+-------------------+-----------------------+-------------+----------+-----------------+---------------------+-------------------+--------------+
```
#### host_summary_by_file_io / x$host_summary_by_file_io
##### Description
Summarizes file IO totals per host.
When the host found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc host_summary_by_file_io;
+------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| ios | decimal(42,0) | YES | | NULL | |
| io_latency | text | YES | | NULL | |
+------------+---------------+------+-----+---------+-------+
3 rows in set (0.00 sec)
mysql> desc x$host_summary_by_file_io;
+------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| ios | decimal(42,0) | YES | | NULL | |
| io_latency | decimal(42,0) | YES | | NULL | |
+------------+---------------+------+-----+---------+-------+
3 rows in set (0.06 sec)
```
##### Example
```SQL
mysql> select * from host_summary_by_file_io;
+------------+-------+------------+
| host | ios | io_latency |
+------------+-------+------------+
| hal1 | 26457 | 21.58 s |
| hal2 | 1189 | 394.21 ms |
+------------+-------+------------+
```
#### host_summary_by_file_io_type / x$host_summary_by_file_io_type
##### Description
Summarizes file IO by event type per host.
When the host found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc host_summary_by_file_io_type;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.70 sec)
mysql> desc x$host_summary_by_file_io_type;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.01 sec)
```
##### Example
```SQL
mysql> select * from host_summary_by_file_io_type;
+------------+--------------------------------------+-------+---------------+-------------+
| host | event_name | total | total_latency | max_latency |
+------------+--------------------------------------+-------+---------------+-------------+
| hal1 | wait/io/file/sql/FRM | 871 | 168.15 ms | 18.48 ms |
| hal1 | wait/io/file/innodb/innodb_data_file | 173 | 129.56 ms | 34.09 ms |
| hal1 | wait/io/file/innodb/innodb_log_file | 20 | 77.53 ms | 60.66 ms |
| hal1 | wait/io/file/myisam/dfile | 40 | 6.54 ms | 4.58 ms |
| hal1 | wait/io/file/mysys/charset | 3 | 4.79 ms | 4.71 ms |
| hal1 | wait/io/file/myisam/kfile | 67 | 4.38 ms | 300.04 us |
| hal1 | wait/io/file/sql/ERRMSG | 5 | 2.72 ms | 1.69 ms |
| hal1 | wait/io/file/sql/pid | 3 | 266.30 us | 185.47 us |
| hal1 | wait/io/file/sql/casetest | 5 | 246.81 us | 150.19 us |
| hal1 | wait/io/file/sql/global_ddl_log | 2 | 21.24 us | 18.59 us |
| hal2 | wait/io/file/sql/file_parser | 1422 | 4.80 s | 135.14 ms |
| hal2 | wait/io/file/sql/FRM | 865 | 85.82 ms | 9.81 ms |
| hal2 | wait/io/file/myisam/kfile | 1073 | 37.14 ms | 15.79 ms |
| hal2 | wait/io/file/myisam/dfile | 2991 | 25.53 ms | 5.25 ms |
| hal2 | wait/io/file/sql/dbopt | 20 | 1.07 ms | 153.07 us |
| hal2 | wait/io/file/sql/misc | 4 | 59.71 us | 33.75 us |
| hal2 | wait/io/file/archive/data | 1 | 13.91 us | 13.91 us |
+------------+--------------------------------------+-------+---------------+-------------+
```
#### host_summary_by_stages / x$host_summary_by_stages
##### Description
Summarizes stages by host, ordered by host and total latency per stage.
When the host found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc host_summary_by_stages;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.06 sec)
mysql> desc x$host_summary_by_stages;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.81 sec)
```
##### Example
```SQL
mysql> select * from host_summary_by_stages;
+------+--------------------------------+-------+---------------+-------------+
| host | event_name | total | total_latency | avg_latency |
+------+--------------------------------+-------+---------------+-------------+
| hal | stage/sql/Opening tables | 889 | 1.97 ms | 2.22 us |
| hal | stage/sql/Creating sort index | 4 | 1.79 ms | 446.30 us |
| hal | stage/sql/init | 10 | 312.27 us | 31.23 us |
| hal | stage/sql/checking permissions | 10 | 300.62 us | 30.06 us |
| hal | stage/sql/freeing items | 5 | 85.89 us | 17.18 us |
| hal | stage/sql/statistics | 5 | 79.15 us | 15.83 us |
| hal | stage/sql/preparing | 5 | 69.12 us | 13.82 us |
| hal | stage/sql/optimizing | 5 | 53.11 us | 10.62 us |
| hal | stage/sql/Sending data | 5 | 44.66 us | 8.93 us |
| hal | stage/sql/closing tables | 5 | 37.54 us | 7.51 us |
| hal | stage/sql/System lock | 5 | 34.28 us | 6.86 us |
| hal | stage/sql/query end | 5 | 24.37 us | 4.87 us |
| hal | stage/sql/end | 5 | 8.60 us | 1.72 us |
| hal | stage/sql/Sorting result | 5 | 8.33 us | 1.67 us |
| hal | stage/sql/executing | 5 | 5.37 us | 1.07 us |
| hal | stage/sql/cleaning up | 5 | 4.60 us | 919.00 ns |
+------+--------------------------------+-------+---------------+-------------+
```
#### host_summary_by_statement_latency / x$host_summary_by_statement_latency
##### Description
Summarizes overall statement statistics by host.
When the host found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc host_summary_by_statement_latency;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_sent | decimal(42,0) | YES | | NULL | |
| rows_examined | decimal(42,0) | YES | | NULL | |
| rows_affected | decimal(42,0) | YES | | NULL | |
| full_scans | decimal(43,0) | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
9 rows in set (0.29 sec)
mysql> desc x$host_summary_by_statement_latency;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | decimal(42,0) | YES | | NULL | |
| max_latency | decimal(42,0) | YES | | NULL | |
| lock_latency | decimal(42,0) | YES | | NULL | |
| rows_sent | decimal(42,0) | YES | | NULL | |
| rows_examined | decimal(42,0) | YES | | NULL | |
| rows_affected | decimal(42,0) | YES | | NULL | |
| full_scans | decimal(43,0) | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
9 rows in set (0.54 sec)
```
##### Example
```SQL
mysql> select * from host_summary_by_statement_latency;
+------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| host | total | total_latency | max_latency | lock_latency | rows_sent | rows_examined | rows_affected | full_scans |
+------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| hal | 3381 | 00:02:09.13 | 1.48 s | 1.07 s | 1151 | 93947 | 150 | 91 |
+------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
```
#### host_summary_by_statement_type / x$host_summary_by_statement_type
##### Description
Summarizes the types of statements executed by each host.
When the host found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc host_summary_by_statement_type;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| statement | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_affected | bigint(20) unsigned | NO | | NULL | |
| full_scans | bigint(21) unsigned | NO | | 0 | |
+---------------+---------------------+------+-----+---------+-------+
10 rows in set (0.30 sec)
mysql> desc x$host_summary_by_statement_type;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| statement | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
| lock_latency | bigint(20) unsigned | NO | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_affected | bigint(20) unsigned | NO | | NULL | |
| full_scans | bigint(21) unsigned | NO | | 0 | |
+---------------+---------------------+------+-----+---------+-------+
10 rows in set (0.76 sec)
```
##### Example
```SQL
mysql> select * from host_summary_by_statement_type;
+------+----------------------+--------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| host | statement | total | total_latency | max_latency | lock_latency | rows_sent | rows_examined | rows_affected | full_scans |
+------+----------------------+--------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| hal | create_view | 2063 | 00:05:04.20 | 463.58 ms | 1.42 s | 0 | 0 | 0 | 0 |
| hal | select | 174 | 40.87 s | 28.83 s | 858.13 ms | 5212 | 157022 | 0 | 82 |
| hal | stmt | 6645 | 15.31 s | 491.78 ms | 0 ps | 0 | 0 | 7951 | 0 |
| hal | call_procedure | 17 | 4.78 s | 1.02 s | 37.94 ms | 0 | 0 | 19 | 0 |
| hal | create_table | 19 | 3.04 s | 431.71 ms | 0 ps | 0 | 0 | 0 | 0 |
...
+------+----------------------+--------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
```
#### innodb_buffer_stats_by_schema / x$innodb_buffer_stats_by_schema
##### Description
Summarizes the output of the INFORMATION_SCHEMA.INNODB_BUFFER_PAGE table, aggregating by schema.
##### Structures
```SQL
mysql> desc innodb_buffer_stats_by_schema;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| object_schema | text | YES | | NULL | |
| allocated | text | YES | | NULL | |
| data | text | YES | | NULL | |
| pages | bigint(21) | NO | | 0 | |
| pages_hashed | bigint(21) | NO | | 0 | |
| pages_old | bigint(21) | NO | | 0 | |
| rows_cached | decimal(44,0) | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
7 rows in set (0.08 sec)
mysql> desc x$innodb_buffer_stats_by_schema;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| object_schema | text | YES | | NULL | |
| allocated | decimal(43,0) | YES | | NULL | |
| data | decimal(43,0) | YES | | NULL | |
| pages | bigint(21) | NO | | 0 | |
| pages_hashed | bigint(21) | NO | | 0 | |
| pages_old | bigint(21) | NO | | 0 | |
| rows_cached | decimal(44,0) | NO | | 0 | |
+---------------+---------------+------+-----+---------+-------+
7 rows in set (0.12 sec)
````
##### Example
```SQL
mysql> select * from innodb_buffer_stats_by_schema;
+--------------------------+------------+------------+-------+--------------+-----------+-------------+
| object_schema | allocated | data | pages | pages_hashed | pages_old | rows_cached |
+--------------------------+------------+------------+-------+--------------+-----------+-------------+
| mem30_trunk__instruments | 1.69 MiB | 510.03 KiB | 108 | 108 | 108 | 3885 |
| InnoDB System | 688.00 KiB | 351.62 KiB | 43 | 43 | 43 | 862 |
| mem30_trunk__events | 80.00 KiB | 21.61 KiB | 5 | 5 | 5 | 229 |
+--------------------------+------------+------------+-------+--------------+-----------+-------------+
```
#### innodb_buffer_stats_by_table / x$innodb_buffer_stats_by_table
##### Description
Summarizes the output of the INFORMATION_SCHEMA.INNODB_BUFFER_PAGE table, aggregating by schema and table name.
##### Structures
```SQL
mysql> desc innodb_buffer_stats_by_table;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| object_schema | text | YES | | NULL | |
| object_name | text | YES | | NULL | |
| allocated | text | YES | | NULL | |
| data | text | YES | | NULL | |
| pages | bigint(21) | NO | | 0 | |
| pages_hashed | bigint(21) | NO | | 0 | |
| pages_old | bigint(21) | NO | | 0 | |
| rows_cached | decimal(44,0) | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
8 rows in set (0.09 sec)
mysql> desc x$innodb_buffer_stats_by_table;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| object_schema | text | YES | | NULL | |
| object_name | text | YES | | NULL | |
| allocated | decimal(43,0) | YES | | NULL | |
| data | decimal(43,0) | YES | | NULL | |
| pages | bigint(21) | NO | | 0 | |
| pages_hashed | bigint(21) | NO | | 0 | |
| pages_old | bigint(21) | NO | | 0 | |
| rows_cached | decimal(44,0) | NO | | 0 | |
+---------------+---------------+------+-----+---------+-------+
8 rows in set (0.18 sec)
```
##### Example
```SQL
mysql> select * from innodb_buffer_stats_by_table;
+--------------------------+------------------------------------+------------+-----------+-------+--------------+-----------+-------------+
| object_schema | object_name | allocated | data | pages | pages_hashed | pages_old | rows_cached |
+--------------------------+------------------------------------+------------+-----------+-------+--------------+-----------+-------------+
| InnoDB System | SYS_COLUMNS | 128.00 KiB | 98.97 KiB | 8 | 8 | 8 | 1532 |
| InnoDB System | SYS_FOREIGN | 128.00 KiB | 55.48 KiB | 8 | 8 | 8 | 172 |
| InnoDB System | SYS_TABLES | 128.00 KiB | 56.18 KiB | 8 | 8 | 8 | 365 |
| InnoDB System | SYS_INDEXES | 112.00 KiB | 76.16 KiB | 7 | 7 | 7 | 1046 |
| mem30_trunk__instruments | agentlatencytime | 96.00 KiB | 28.83 KiB | 6 | 6 | 6 | 252 |
| mem30_trunk__instruments | binlogspaceusagedata | 96.00 KiB | 22.54 KiB | 6 | 6 | 6 | 196 |
| mem30_trunk__instruments | connectionsdata | 96.00 KiB | 36.68 KiB | 6 | 6 | 6 | 276 |
| mem30_trunk__instruments | connectionsmaxdata | 96.00 KiB | 31.88 KiB | 6 | 6 | 6 | 271 |
| mem30_trunk__instruments | cpuaverage | 96.00 KiB | 14.32 KiB | 6 | 6 | 6 | 55 |
| mem30_trunk__instruments | diskiototaldata | 96.00 KiB | 42.71 KiB | 6 | 6 | 6 | 152 |
| mem30_trunk__instruments | innodbopenfilesdata | 96.00 KiB | 32.61 KiB | 6 | 6 | 6 | 266 |
| mem30_trunk__instruments | innodbrowlocktimestatisticsdata | 96.00 KiB | 32.16 KiB | 6 | 6 | 6 | 261 |
| mem30_trunk__instruments | myisamkeybufferusagedata | 96.00 KiB | 25.99 KiB | 6 | 6 | 6 | 232 |
| mem30_trunk__instruments | mysqlprocessactivity | 96.00 KiB | 31.99 KiB | 6 | 6 | 6 | 252 |
| mem30_trunk__instruments | querycacheaveragefreeblocksizedata | 96.00 KiB | 27.00 KiB | 6 | 6 | 6 | 237 |
| mem30_trunk__instruments | querycacheaveragequerysizedata | 96.00 KiB | 38.29 KiB | 6 | 6 | 6 | 315 |
| mem30_trunk__instruments | querycachefragmentationdata | 96.00 KiB | 27.00 KiB | 6 | 6 | 6 | 237 |
| mem30_trunk__instruments | querycachememorydata | 96.00 KiB | 32.58 KiB | 6 | 6 | 6 | 278 |
| mem30_trunk__instruments | querycachequeriesincachedata | 96.00 KiB | 27.15 KiB | 6 | 6 | 6 | 238 |
| mem30_trunk__instruments | ramusagedata | 96.00 KiB | 15.02 KiB | 6 | 6 | 6 | 59 |
| mem30_trunk__instruments | slaverelaylogspaceusagedata | 96.00 KiB | 28.28 KiB | 6 | 6 | 6 | 249 |
| mem30_trunk__instruments | swapusagedata | 96.00 KiB | 15.02 KiB | 6 | 6 | 6 | 59 |
| InnoDB System | SYS_FIELDS | 80.00 KiB | 49.78 KiB | 5 | 5 | 5 | 1147 |
| InnoDB System | SYS_DATAFILES | 32.00 KiB | 3.97 KiB | 2 | 2 | 2 | 60 |
| InnoDB System | SYS_FOREIGN_COLS | 32.00 KiB | 7.43 KiB | 2 | 2 | 2 | 83 |
| InnoDB System | SYS_TABLESPACES | 32.00 KiB | 3.65 KiB | 2 | 2 | 2 | 56 |
| InnoDB System | SYS_IBUF_TABLE | 16.00 KiB | 0 bytes | 1 | 1 | 1 | 0 |
+--------------------------+------------------------------------+------------+-----------+-------+--------------+-----------+-------------+
```
#### innodb_lock_waits / x$innodb_lock_waits
##### Description
Gives a snapshot of which InnoDB locks transactions are waiting for.
The lock waits are ordered by the age of the lock descending.
##### Structures
```SQL
mysql> desc sys.innodb_lock_waits;
+------------------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------------+---------------------+------+-----+---------------------+-------+
| wait_started | datetime | YES | | NULL | |
| wait_age | time | YES | | NULL | |
| wait_age_secs | bigint(21) | YES | | NULL | |
| locked_table | varchar(1024) | NO | | | |
| locked_index | varchar(1024) | YES | | NULL | |
| locked_type | varchar(32) | NO | | | |
| waiting_trx_id | varchar(18) | NO | | | |
| waiting_trx_started | datetime | NO | | 0000-00-00 00:00:00 | |
| waiting_trx_age | time | YES | | NULL | |
| waiting_trx_rows_locked | bigint(21) unsigned | NO | | 0 | |
| waiting_trx_rows_modified | bigint(21) unsigned | NO | | 0 | |
| waiting_pid | bigint(21) unsigned | NO | | 0 | |
| waiting_query | longtext | YES | | NULL | |
| waiting_lock_id | varchar(81) | NO | | | |
| waiting_lock_mode | varchar(32) | NO | | | |
| blocking_trx_id | varchar(18) | NO | | | |
| blocking_pid | bigint(21) unsigned | NO | | 0 | |
| blocking_query | longtext | YES | | NULL | |
| blocking_lock_id | varchar(81) | NO | | | |
| blocking_lock_mode | varchar(32) | NO | | | |
| blocking_trx_started | datetime | NO | | 0000-00-00 00:00:00 | |
| blocking_trx_age | time | YES | | NULL | |
| blocking_trx_rows_locked | bigint(21) unsigned | NO | | 0 | |
| blocking_trx_rows_modified | bigint(21) unsigned | NO | | 0 | |
| sql_kill_blocking_query | varchar(32) | YES | | NULL | |
| sql_kill_blocking_connection | varchar(26) | YES | | NULL | |
+------------------------------+---------------------+------+-----+---------------------+-------+
26 rows in set (0.01 sec)
mysql> desc sys.x$innodb_lock_waits;
+------------------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------------+---------------------+------+-----+---------------------+-------+
| wait_started | datetime | YES | | NULL | |
| wait_age | time | YES | | NULL | |
| wait_age_secs | bigint(21) | YES | | NULL | |
| locked_table | varchar(1024) | NO | | | |
| locked_index | varchar(1024) | YES | | NULL | |
| locked_type | varchar(32) | NO | | | |
| waiting_trx_id | varchar(18) | NO | | | |
| waiting_trx_started | datetime | NO | | 0000-00-00 00:00:00 | |
| waiting_trx_age | time | YES | | NULL | |
| waiting_trx_rows_locked | bigint(21) unsigned | NO | | 0 | |
| waiting_trx_rows_modified | bigint(21) unsigned | NO | | 0 | |
| waiting_pid | bigint(21) unsigned | NO | | 0 | |
| waiting_query | varchar(1024) | YES | | NULL | |
| waiting_lock_id | varchar(81) | NO | | | |
| waiting_lock_mode | varchar(32) | NO | | | |
| blocking_trx_id | varchar(18) | NO | | | |
| blocking_pid | bigint(21) unsigned | NO | | 0 | |
| blocking_query | varchar(1024) | YES | | NULL | |
| blocking_lock_id | varchar(81) | NO | | | |
| blocking_lock_mode | varchar(32) | NO | | | |
| blocking_trx_started | datetime | NO | | 0000-00-00 00:00:00 | |
| blocking_trx_age | time | YES | | NULL | |
| blocking_trx_rows_locked | bigint(21) unsigned | NO | | 0 | |
| blocking_trx_rows_modified | bigint(21) unsigned | NO | | 0 | |
| sql_kill_blocking_query | varchar(32) | YES | | NULL | |
| sql_kill_blocking_connection | varchar(26) | YES | | NULL | |
+------------------------------+---------------------+------+-----+---------------------+-------+
26 rows in set (0.02 sec)
```
##### Example
```SQL
mysql> SELECT * FROM innodb_lock_waits\G
*************************** 1. row ***************************
wait_started: 2014-11-11 13:39:20
wait_age: 00:00:07
wait_age_secs: 7
locked_table: `db1`.`t1`
locked_index: PRIMARY
locked_type: RECORD
waiting_trx_id: 867158
waiting_trx_started: 2014-11-11 13:39:15
waiting_trx_age: 00:00:12
waiting_trx_rows_locked: 0
waiting_trx_rows_modified: 0
waiting_pid: 3
waiting_query: UPDATE t1 SET val = val + 1 WHERE id = 2
waiting_lock_id: 867158:2363:3:3
waiting_lock_mode: X
blocking_trx_id: 867157
blocking_pid: 4
blocking_query: UPDATE t1 SET val = val + 1 + SLEEP(10) WHERE id = 2
blocking_lock_id: 867157:2363:3:3
blocking_lock_mode: X
blocking_trx_started: 2014-11-11 13:39:11
blocking_trx_age: 00:00:16
blocking_trx_rows_locked: 1
blocking_trx_rows_modified: 1
sql_kill_blocking_query: KILL QUERY 4
sql_kill_blocking_connection: KILL 4
```
#### io_by_thread_by_latency / x$io_by_thread_by_latency
##### Description
Shows the top IO consumers by thread, ordered by total latency.
##### Structures
```SQL
mysql> desc io_by_thread_by_latency;
+----------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+---------------------+------+-----+---------+-------+
| user | varchar(128) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | text | YES | | NULL | |
| min_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| thread_id | bigint(20) unsigned | NO | | NULL | |
| processlist_id | bigint(20) unsigned | YES | | NULL | |
+----------------+---------------------+------+-----+---------+-------+
8 rows in set (0.14 sec)
mysql> desc x$io_by_thread_by_latency;
+----------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+---------------------+------+-----+---------+-------+
| user | varchar(128) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | decimal(42,0) | YES | | NULL | |
| min_latency | bigint(20) unsigned | YES | | NULL | |
| avg_latency | decimal(24,4) | YES | | NULL | |
| max_latency | bigint(20) unsigned | YES | | NULL | |
| thread_id | bigint(20) unsigned | NO | | NULL | |
| processlist_id | bigint(20) unsigned | YES | | NULL | |
+----------------+---------------------+------+-----+---------+-------+
8 rows in set (0.03 sec)
```
##### Example
```SQL
mysql> select * from io_by_thread_by_latency;
+---------------------+-------+---------------+-------------+-------------+-------------+-----------+----------------+
| user | total | total_latency | min_latency | avg_latency | max_latency | thread_id | processlist_id |
+---------------------+-------+---------------+-------------+-------------+-------------+-----------+----------------+
| root@localhost | 11580 | 18.01 s | 429.78 ns | 1.12 ms | 181.07 ms | 25 | 6 |
| main | 1358 | 1.31 s | 475.02 ns | 2.27 ms | 350.70 ms | 1 | NULL |
| page_cleaner_thread | 654 | 147.44 ms | 588.12 ns | 225.44 us | 46.41 ms | 18 | NULL |
| io_write_thread | 131 | 107.75 ms | 8.60 us | 822.55 us | 27.69 ms | 8 | NULL |
| io_write_thread | 46 | 47.07 ms | 10.64 us | 1.02 ms | 16.90 ms | 9 | NULL |
| io_write_thread | 71 | 46.99 ms | 9.11 us | 661.81 us | 17.04 ms | 11 | NULL |
| io_log_thread | 20 | 21.01 ms | 14.25 us | 1.05 ms | 7.08 ms | 3 | NULL |
| srv_master_thread | 13 | 17.60 ms | 8.49 us | 1.35 ms | 9.99 ms | 16 | NULL |
| srv_purge_thread | 4 | 1.81 ms | 34.31 us | 452.45 us | 1.02 ms | 17 | NULL |
| io_write_thread | 19 | 951.39 us | 9.75 us | 50.07 us | 297.47 us | 10 | NULL |
| signal_handler | 3 | 218.03 us | 21.64 us | 72.68 us | 154.84 us | 19 | NULL |
+---------------------+-------+---------------+-------------+-------------+-------------+-----------+----------------+
```
#### io_global_by_file_by_bytes / x$io_global_by_file_by_bytes
##### Description
Shows the top global IO consumers by bytes usage by file.
##### Structures
```SQL
mysql> desc io_global_by_file_by_bytes;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| file | varchar(512) | YES | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| total_read | text | YES | | NULL | |
| avg_read | text | YES | | NULL | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| total_written | text | YES | | NULL | |
| avg_write | text | YES | | NULL | |
| total | text | YES | | NULL | |
| write_pct | decimal(26,2) | NO | | 0.00 | |
+---------------+---------------------+------+-----+---------+-------+
9 rows in set (0.15 sec)
mysql> desc x$io_global_by_file_by_bytes;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| file | varchar(512) | NO | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| total_read | bigint(20) | NO | | NULL | |
| avg_read | decimal(23,4) | NO | | 0.0000 | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| total_written | bigint(20) | NO | | NULL | |
| avg_write | decimal(23,4) | NO | | 0.0000 | |
| total | bigint(21) | NO | | 0 | |
| write_pct | decimal(26,2) | NO | | 0.00 | |
+---------------+---------------------+------+-----+---------+-------+
9 rows in set (0.14 sec)
```
##### Example
```SQL
mysql> SELECT * FROM io_global_by_file_by_bytes LIMIT 5;
+--------------------------------------------+------------+------------+-----------+-------------+---------------+-----------+------------+-----------+
| file | count_read | total_read | avg_read | count_write | total_written | avg_write | total | write_pct |
+--------------------------------------------+------------+------------+-----------+-------------+---------------+-----------+------------+-----------+
| @@datadir/ibdata1 | 147 | 4.27 MiB | 29.71 KiB | 3 | 48.00 KiB | 16.00 KiB | 4.31 MiB | 1.09 |
| @@datadir/mysql/proc.MYD | 347 | 85.35 KiB | 252 bytes | 111 | 19.08 KiB | 176 bytes | 104.43 KiB | 18.27 |
| @@datadir/ib_logfile0 | 6 | 68.00 KiB | 11.33 KiB | 8 | 4.00 KiB | 512 bytes | 72.00 KiB | 5.56 |
| /opt/mysql/5.5.33/share/english/errmsg.sys | 3 | 43.68 KiB | 14.56 KiB | 0 | 0 bytes | 0 bytes | 43.68 KiB | 0.00 |
| /opt/mysql/5.5.33/share/charsets/Index.xml | 1 | 17.89 KiB | 17.89 KiB | 0 | 0 bytes | 0 bytes | 17.89 KiB | 0.00 |
+--------------------------------------------+------------+------------+-----------+-------------+---------------+-----------+------------+-----------+
```
#### io_global_by_file_by_latency / x$io_global_by_file_by_latency
##### Description
Shows the top global IO consumers by latency by file.
##### Structures
```SQL
mysql> desc io_global_by_file_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| file | varchar(512) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| read_latency | text | YES | | NULL | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| write_latency | text | YES | | NULL | |
| count_misc | bigint(20) unsigned | NO | | NULL | |
| misc_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
9 rows in set (0.00 sec)
mysql> desc x$io_global_by_file_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| file | varchar(512) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| read_latency | bigint(20) unsigned | NO | | NULL | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| write_latency | bigint(20) unsigned | NO | | NULL | |
| count_misc | bigint(20) unsigned | NO | | NULL | |
| misc_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
9 rows in set (0.07 sec)
```
##### Example
```SQL
mysql> select * from io_global_by_file_by_latency limit 5;
+-----------------------------------------------------------+-------+---------------+------------+--------------+-------------+---------------+------------+--------------+
| file | total | total_latency | count_read | read_latency | count_write | write_latency | count_misc | misc_latency |
+-----------------------------------------------------------+-------+---------------+------------+--------------+-------------+---------------+------------+--------------+
| @@datadir/sys/wait_classes_global_by_avg_latency_raw.frm~ | 24 | 451.99 ms | 0 | 0 ps | 4 | 108.07 us | 20 | 451.88 ms |
| @@datadir/sys/innodb_buffer_stats_by_schema_raw.frm~ | 24 | 379.84 ms | 0 | 0 ps | 4 | 108.88 us | 20 | 379.73 ms |
| @@datadir/sys/io_by_thread_by_latency_raw.frm~ | 24 | 379.46 ms | 0 | 0 ps | 4 | 101.37 us | 20 | 379.36 ms |
| @@datadir/ibtmp1 | 53 | 373.45 ms | 0 | 0 ps | 48 | 246.08 ms | 5 | 127.37 ms |
| @@datadir/sys/statement_analysis_raw.frm~ | 24 | 353.14 ms | 0 | 0 ps | 4 | 94.96 us | 20 | 353.04 ms |
+-----------------------------------------------------------+-------+---------------+------------+--------------+-------------+---------------+------------+--------------+
```
#### io_global_by_wait_by_bytes / x$io_global_by_wait_by_bytes
##### Description
Shows the top global IO consumer classes by bytes usage.
##### Structures
```SQL
mysql> desc io_global_by_wait_by_bytes;
+-----------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+---------------------+------+-----+---------+-------+
| event_name | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| min_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| total_read | text | YES | | NULL | |
| avg_read | text | YES | | NULL | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| total_written | text | YES | | NULL | |
| avg_written | text | YES | | NULL | |
| total_requested | text | YES | | NULL | |
+-----------------+---------------------+------+-----+---------+-------+
13 rows in set (0.02 sec)
mysql> desc x$io_global_by_wait_by_bytes;
+-----------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+---------------------+------+-----+---------+-------+
| event_name | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| min_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| total_read | bigint(20) | NO | | NULL | |
| avg_read | decimal(23,4) | NO | | 0.0000 | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| total_written | bigint(20) | NO | | NULL | |
| avg_written | decimal(23,4) | NO | | 0.0000 | |
| total_requested | bigint(21) | NO | | 0 | |
+-----------------+---------------------+------+-----+---------+-------+
13 rows in set (0.01 sec)
```
##### Example
```SQL
mysql> select * from io_global_by_wait_by_bytes;
+--------------------+--------+---------------+-------------+-------------+-------------+------------+------------+-----------+-------------+---------------+-------------+-----------------+
| event_name | total | total_latency | min_latency | avg_latency | max_latency | count_read | total_read | avg_read | count_write | total_written | avg_written | total_requested |
+--------------------+--------+---------------+-------------+-------------+-------------+------------+------------+-----------+-------------+---------------+-------------+-----------------+
| myisam/dfile | 163681 | 983.13 ms | 379.08 ns | 6.01 us | 22.06 ms | 68737 | 127.31 MiB | 1.90 KiB | 1012221 | 121.52 MiB | 126 bytes | 248.83 MiB |
| myisam/kfile | 1775 | 375.13 ms | 1.02 us | 211.34 µs | 35.15 ms | 54066 | 9.97 MiB | 193 bytes | 428257 | 12.40 MiB | 30 bytes | 22.37 MiB |
| sql/FRM | 57889 | 8.40 s | 19.44 ns | 145.05 us | 336.71 ms | 8009 | 2.60 MiB | 341 bytes | 14675 | 2.91 MiB | 208 bytes | 5.51 MiB |
| sql/global_ddl_log | 164 | 75.96 ms | 5.72 us | 463.19 µs | 7.43 ms | 20 | 80.00 KiB | 4.00 KiB | 76 | 304.00 KiB | 4.00 KiB | 384.00 KiB |
| sql/file_parser | 419 | 601.37 ms | 1.96 us | 1.44 ms | 37.14 ms | 66 | 42.01 KiB | 652 bytes | 64 | 226.98 KiB | 3.55 KiB | 268.99 KiB |
| sql/binlog | 190 | 6.79 s | 1.56 us | 35.76 ms | 4.21 s | 52 | 60.54 KiB | 1.16 KiB | 0 | 0 bytes | 0 bytes | 60.54 KiB |
| sql/ERRMSG | 5 | 2.03 s | 8.61 us | 405.40 ms | 2.03 s | 3 | 51.82 KiB | 17.27 KiB | 0 | 0 bytes | 0 bytes | 51.82 KiB |
| mysys/charset | 3 | 196.52 us | 17.61 µs | 65.51 µs | 137.33 µs | 1 | 17.83 KiB | 17.83 KiB | 0 | 0 bytes | 0 bytes | 17.83 KiB |
| sql/partition | 81 | 18.87 ms | 888.08 ns | 232.92 us | 4.67 ms | 66 | 2.75 KiB | 43 bytes | 8 | 288 bytes | 36 bytes | 3.04 KiB |
| sql/dbopt | 329166 | 26.95 s | 2.06 us | 81.89 µs | 178.71 ms | 0 | 0 bytes | 0 bytes | 9 | 585 bytes | 65 bytes | 585 bytes |
| sql/relaylog | 7 | 1.18 ms | 838.84 ns | 168.30 us | 892.70 µs | 0 | 0 bytes | 0 bytes | 1 | 120 bytes | 120 bytes | 120 bytes |
| mysys/cnf | 5 | 171.61 us | 303.26 ns | 34.32 µs | 115.21 µs | 3 | 56 bytes | 19 bytes | 0 | 0 bytes | 0 bytes | 56 bytes |
| sql/pid | 3 | 220.55 us | 29.29 µs | 73.52 µs | 143.11 µs | 0 | 0 bytes | 0 bytes | 1 | 5 bytes | 5 bytes | 5 bytes |
| sql/casetest | 1 | 121.19 us | 121.19 µs | 121.19 µs | 121.19 µs | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes | 0 bytes |
| sql/binlog_index | 5 | 593.47 us | 1.07 µs | 118.69 µs | 535.90 µs | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes | 0 bytes |
| sql/misc | 23 | 2.73 ms | 65.14 us | 118.50 µs | 255.31 µs | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes | 0 bytes |
+--------------------+--------+---------------+-------------+-------------+-------------+------------+------------+-----------+-------------+---------------+-------------+-----------------+
```
#### io_global_by_wait_by_latency / x$io_global_by_wait_by_latency
##### Description
Shows the top global IO consumers by latency.
##### Structures
```SQL
mysql> desc io_global_by_wait_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| event_name | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| read_latency | text | YES | | NULL | |
| write_latency | text | YES | | NULL | |
| misc_latency | text | YES | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| total_read | text | YES | | NULL | |
| avg_read | text | YES | | NULL | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| total_written | text | YES | | NULL | |
| avg_written | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
14 rows in set (0.19 sec)
mysql> desc x$io_global_by_wait_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| event_name | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
| read_latency | bigint(20) unsigned | NO | | NULL | |
| write_latency | bigint(20) unsigned | NO | | NULL | |
| misc_latency | bigint(20) unsigned | NO | | NULL | |
| count_read | bigint(20) unsigned | NO | | NULL | |
| total_read | bigint(20) | NO | | NULL | |
| avg_read | decimal(23,4) | NO | | 0.0000 | |
| count_write | bigint(20) unsigned | NO | | NULL | |
| total_written | bigint(20) | NO | | NULL | |
| avg_written | decimal(23,4) | NO | | 0.0000 | |
+---------------+---------------------+------+-----+---------+-------+
14 rows in set (0.01 sec)
```
##### Example
```SQL
mysql> SELECT * FROM io_global_by_wait_by_latency;
+-------------------------+-------+---------------+-------------+-------------+--------------+---------------+--------------+------------+------------+-----------+-------------+---------------+-------------+
| event_name | total | total_latency | avg_latency | max_latency | read_latency | write_latency | misc_latency | count_read | total_read | avg_read | count_write | total_written | avg_written |
+-------------------------+-------+---------------+-------------+-------------+--------------+---------------+--------------+------------+------------+-----------+-------------+---------------+-------------+
| sql/file_parser | 5433 | 30.20 s | 5.56 ms | 203.65 ms | 22.08 ms | 24.89 ms | 30.16 s | 24 | 6.18 KiB | 264 bytes | 737 | 2.15 MiB | 2.99 KiB |
| innodb/innodb_data_file | 1344 | 1.52 s | 1.13 ms | 350.70 ms | 203.82 ms | 450.96 ms | 868.21 ms | 147 | 2.30 MiB | 16.00 KiB | 1001 | 53.61 MiB | 54.84 KiB |
| innodb/innodb_log_file | 828 | 893.48 ms | 1.08 ms | 30.11 ms | 16.32 ms | 705.89 ms | 171.27 ms | 6 | 68.00 KiB | 11.33 KiB | 413 | 2.19 MiB | 5.42 KiB |
| myisam/kfile | 7642 | 242.34 ms | 31.71 us | 19.27 ms | 73.60 ms | 23.48 ms | 145.26 ms | 758 | 135.63 KiB | 183 bytes | 4386 | 232.52 KiB | 54 bytes |
| myisam/dfile | 12540 | 223.47 ms | 17.82 us | 32.50 ms | 87.76 ms | 16.97 ms | 118.74 ms | 5390 | 4.49 MiB | 873 bytes | 1448 | 2.65 MiB | 1.88 KiB |
| csv/metadata | 8 | 28.98 ms | 3.62 ms | 20.15 ms | 399.27 us | 0 ps | 28.58 ms | 2 | 70 bytes | 35 bytes | 0 | 0 bytes | 0 bytes |
| mysys/charset | 3 | 24.24 ms | 8.08 ms | 24.15 ms | 24.15 ms | 0 ps | 93.18 us | 1 | 17.31 KiB | 17.31 KiB | 0 | 0 bytes | 0 bytes |
| sql/ERRMSG | 5 | 20.43 ms | 4.09 ms | 19.31 ms | 20.32 ms | 0 ps | 103.20 us | 3 | 58.97 KiB | 19.66 KiB | 0 | 0 bytes | 0 bytes |
| mysys/cnf | 5 | 11.37 ms | 2.27 ms | 11.28 ms | 11.29 ms | 0 ps | 78.22 us | 3 | 56 bytes | 19 bytes | 0 | 0 bytes | 0 bytes |
| sql/dbopt | 57 | 4.04 ms | 70.92 us | 843.70 us | 0 ps | 186.43 us | 3.86 ms | 0 | 0 bytes | 0 bytes | 7 | 431 bytes | 62 bytes |
| csv/data | 4 | 411.55 us | 102.89 us | 234.89 us | 0 ps | 0 ps | 411.55 us | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes |
| sql/misc | 22 | 340.38 us | 15.47 us | 33.77 us | 0 ps | 0 ps | 340.38 us | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes |
| archive/data | 39 | 277.86 us | 7.12 us | 16.18 us | 0 ps | 0 ps | 277.86 us | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes |
| sql/pid | 3 | 218.03 us | 72.68 us | 154.84 us | 0 ps | 21.64 us | 196.39 us | 0 | 0 bytes | 0 bytes | 1 | 6 bytes | 6 bytes |
| sql/casetest | 5 | 197.15 us | 39.43 us | 126.31 us | 0 ps | 0 ps | 197.15 us | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes |
| sql/global_ddl_log | 2 | 14.60 us | 7.30 us | 12.12 us | 0 ps | 0 ps | 14.60 us | 0 | 0 bytes | 0 bytes | 0 | 0 bytes | 0 bytes |
+-------------------------+-------+---------------+-------------+-------------+--------------+---------------+--------------+------------+------------+-----------+-------------+---------------+-------------+
```
#### latest_file_io / x$latest_file_io
##### Description
Shows the latest file IO, by file / thread.
##### Structures
```SQL
mysql> desc latest_file_io;
+-----------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+--------------+------+-----+---------+-------+
| thread | varchar(149) | YES | | NULL | |
| file | varchar(512) | YES | | NULL | |
| latency | text | YES | | NULL | |
| operation | varchar(32) | NO | | NULL | |
| requested | text | YES | | NULL | |
+-----------+--------------+------+-----+---------+-------+
5 rows in set (0.10 sec)
mysql> desc x$latest_file_io;
+-----------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+---------------------+------+-----+---------+-------+
| thread | varchar(149) | YES | | NULL | |
| file | varchar(512) | YES | | NULL | |
| latency | bigint(20) unsigned | YES | | NULL | |
| operation | varchar(32) | NO | | NULL | |
| requested | bigint(20) | YES | | NULL | |
+-----------+---------------------+------+-----+---------+-------+
5 rows in set (0.05 sec)
```
##### Example
```SQL
mysql> select * from latest_file_io limit 5;
+----------------------+----------------------------------------+------------+-----------+-----------+
| thread | file | latency | operation | requested |
+----------------------+----------------------------------------+------------+-----------+-----------+
| msandbox@localhost:1 | @@tmpdir/#sqlcf28_1_4e.MYI | 9.26 us | write | 124 bytes |
| msandbox@localhost:1 | @@tmpdir/#sqlcf28_1_4e.MYI | 4.00 us | write | 2 bytes |
| msandbox@localhost:1 | @@tmpdir/#sqlcf28_1_4e.MYI | 56.34 us | close | NULL |
| msandbox@localhost:1 | @@tmpdir/#sqlcf28_1_4e.MYD | 53.93 us | close | NULL |
| msandbox@localhost:1 | @@tmpdir/#sqlcf28_1_4e.MYI | 104.05 ms | delete | NULL |
+----------------------+----------------------------------------+------------+-----------+-----------+
```
#### memory_by_host_by_current_bytes / x$memory_by_host_by_current_bytes
##### Description
Summarizes memory use by host using the 5.7 Performance Schema instrumentation.
When the host found is NULL, it is assumed to be a local "background" thread.
##### Structures
```SQL
mysql> desc memory_by_host_by_current_bytes;
+--------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| current_count_used | decimal(41,0) | YES | | NULL | |
| current_allocated | text | YES | | NULL | |
| current_avg_alloc | text | YES | | NULL | |
| current_max_alloc | text | YES | | NULL | |
| total_allocated | text | YES | | NULL | |
+--------------------+---------------+------+-----+---------+-------+
6 rows in set (0.24 sec)
mysql> desc x$memory_by_host_by_current_bytes;
+--------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| current_count_used | decimal(41,0) | YES | | NULL | |
| current_allocated | decimal(41,0) | YES | | NULL | |
| current_avg_alloc | decimal(45,4) | NO | | 0.0000 | |
| current_max_alloc | bigint(20) | YES | | NULL | |
| total_allocated | decimal(42,0) | YES | | NULL | |
+--------------------+---------------+------+-----+---------+-------+
6 rows in set (0.28 sec)
```
##### Example
```SQL
mysql> select * from memory_by_host_by_current_bytes WHERE host IS NOT NULL;
+------------+--------------------+-------------------+-------------------+-------------------+-----------------+
| host | current_count_used | current_allocated | current_avg_alloc | current_max_alloc | total_allocated |
+------------+--------------------+-------------------+-------------------+-------------------+-----------------+
| background | 2773 | 10.84 MiB | 4.00 KiB | 8.00 MiB | 30.69 MiB |
| localhost | 1509 | 809.30 KiB | 549 bytes | 176.38 KiB | 83.59 MiB |
+------------+--------------------+-------------------+-------------------+-------------------+-----------------+
```
#### memory_by_thread_by_current_bytes / x$memory_by_thread_by_current_bytes
##### Description
Summarizes memory use by user using the 5.7 Performance Schema instrumentation.
The user columns shows either the background or foreground user name appropriately.
##### Structures
```SQL
mysql> desc memory_by_thread_by_current_bytes;
+--------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------------+------+-----+---------+-------+
| thread_id | bigint(20) unsigned | NO | | NULL | |
| user | varchar(128) | YES | | NULL | |
| current_count_used | decimal(41,0) | YES | | NULL | |
| current_allocated | text | YES | | NULL | |
| current_avg_alloc | text | YES | | NULL | |
| current_max_alloc | text | YES | | NULL | |
| total_allocated | text | YES | | NULL | |
+--------------------+---------------------+------+-----+---------+-------+
7 rows in set (0.49 sec)
mysql> desc x$memory_by_thread_by_current_bytes;
+--------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------------+------+-----+---------+-------+
| thread_id | bigint(20) unsigned | NO | | NULL | |
| user | varchar(128) | YES | | NULL | |
| current_count_used | decimal(41,0) | YES | | NULL | |
| current_allocated | decimal(41,0) | YES | | NULL | |
| current_avg_alloc | decimal(45,4) | NO | | 0.0000 | |
| current_max_alloc | bigint(20) | YES | | NULL | |
| total_allocated | decimal(42,0) | YES | | NULL | |
+--------------------+---------------------+------+-----+---------+-------+
7 rows in set (0.25 sec)
```
##### Example
```SQL
mysql> select * from sys.memory_by_thread_by_current_bytes limit 5;
+-----------+----------------+--------------------+-------------------+-------------------+-------------------+-----------------+
| thread_id | user | current_count_used | current_allocated | current_avg_alloc | current_max_alloc | total_allocated |
+-----------+----------------+--------------------+-------------------+-------------------+-------------------+-----------------+
| 1 | sql/main | 29333 | 166.02 MiB | 5.80 KiB | 131.13 MiB | 196.00 MiB |
| 55 | root@localhost | 175 | 1.04 MiB | 6.09 KiB | 350.86 KiB | 67.37 MiB |
| 58 | root@localhost | 236 | 368.13 KiB | 1.56 KiB | 312.05 KiB | 130.34 MiB |
| 904 | root@localhost | 32 | 18.00 KiB | 576 bytes | 16.00 KiB | 6.68 MiB |
| 970 | root@localhost | 12 | 16.80 KiB | 1.40 KiB | 16.00 KiB | 1.20 MiB |
+-----------+----------------+--------------------+-------------------+-------------------+-------------------+-----------------+
```
#### memory_by_user_by_current_bytes / x$memory_by_user_by_current_bytes
##### Description
Summarizes memory use by user using the 5.7 Performance Schema instrumentation.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc memory_by_user_by_current_bytes;
+--------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| current_count_used | decimal(41,0) | YES | | NULL | |
| current_allocated | text | YES | | NULL | |
| current_avg_alloc | text | YES | | NULL | |
| current_max_alloc | text | YES | | NULL | |
| total_allocated | text | YES | | NULL | |
+--------------------+---------------+------+-----+---------+-------+
6 rows in set (0.06 sec)
mysql> desc x$memory_by_user_by_current_bytes;
+--------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| current_count_used | decimal(41,0) | YES | | NULL | |
| current_allocated | decimal(41,0) | YES | | NULL | |
| current_avg_alloc | decimal(45,4) | NO | | 0.0000 | |
| current_max_alloc | bigint(20) | YES | | NULL | |
| total_allocated | decimal(42,0) | YES | | NULL | |
+--------------------+---------------+------+-----+---------+-------+
6 rows in set (0.12 sec)
```
##### Example
```SQL
mysql> select * from memory_by_user_by_current_bytes;
+------+--------------------+-------------------+-------------------+-------------------+-----------------+
| user | current_count_used | current_allocated | current_avg_alloc | current_max_alloc | total_allocated |
+------+--------------------+-------------------+-------------------+-------------------+-----------------+
| root | 1401 | 1.09 MiB | 815 bytes | 334.97 KiB | 42.73 MiB |
| mark | 201 | 496.08 KiB | 2.47 KiB | 334.97 KiB | 5.50 MiB |
+------+--------------------+-------------------+-------------------+-------------------+-----------------+
```
#### memory_global_by_current_bytes / x$memory_global_by_current_bytes
##### Description
Shows the current memory usage within the server globally broken down by allocation type.
##### Structures
```SQL
mysql> desc memory_global_by_current_bytes;
+-------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+--------------+------+-----+---------+-------+
| event_name | varchar(128) | NO | | NULL | |
| current_count | bigint(20) | NO | | NULL | |
| current_alloc | text | YES | | NULL | |
| current_avg_alloc | text | YES | | NULL | |
| high_count | bigint(20) | NO | | NULL | |
| high_alloc | text | YES | | NULL | |
| high_avg_alloc | text | YES | | NULL | |
+-------------------+--------------+------+-----+---------+-------+
7 rows in set (0.08 sec)
mysql> desc x$memory_global_by_current_bytes;
+-------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------+------+-----+---------+-------+
| event_name | varchar(128) | NO | | NULL | |
| current_count | bigint(20) | NO | | NULL | |
| current_alloc | bigint(20) | NO | | NULL | |
| current_avg_alloc | decimal(23,4) | NO | | 0.0000 | |
| high_count | bigint(20) | NO | | NULL | |
| high_alloc | bigint(20) | NO | | NULL | |
| high_avg_alloc | decimal(23,4) | NO | | 0.0000 | |
+-------------------+---------------+------+-----+---------+-------+
7 rows in set (0.16 sec)
```
##### Example
```SQL
mysql> select * from memory_global_by_current_bytes;
+----------------------------------------+---------------+---------------+-------------------+------------+------------+----------------+
| event_name | current_count | current_alloc | current_avg_alloc | high_count | high_alloc | high_avg_alloc |
+----------------------------------------+---------------+---------------+-------------------+------------+------------+----------------+
| memory/sql/TABLE_SHARE::mem_root | 269 | 568.21 KiB | 2.11 KiB | 339 | 706.04 KiB | 2.08 KiB |
| memory/sql/TABLE | 214 | 366.56 KiB | 1.71 KiB | 245 | 481.13 KiB | 1.96 KiB |
| memory/sql/sp_head::main_mem_root | 32 | 334.97 KiB | 10.47 KiB | 421 | 9.73 MiB | 23.66 KiB |
| memory/sql/Filesort_buffer::sort_keys | 1 | 255.89 KiB | 255.89 KiB | 1 | 256.00 KiB | 256.00 KiB |
| memory/mysys/array_buffer | 82 | 121.66 KiB | 1.48 KiB | 1124 | 852.55 KiB | 777 bytes |
...
+----------------------------------------+---------------+---------------+-------------------+------------+------------+----------------+
```
#### memory_global_total / x$memory_global_total
##### Description
Shows the total memory usage within the server globally.
##### Structures
```SQL
mysql> desc memory_global_total;
+-----------------+------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+------+------+-----+---------+-------+
| total_allocated | text | YES | | NULL | |
+-----------------+------+------+-----+---------+-------+
1 row in set (0.07 sec)
mysql> desc x$memory_global_total;
+-----------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+---------------+------+-----+---------+-------+
| total_allocated | decimal(41,0) | YES | | NULL | |
+-----------------+---------------+------+-----+---------+-------+
1 row in set (0.00 sec)
```
##### Example
```SQL
mysql> select * from memory_global_total;
+-----------------+
| total_allocated |
+-----------------+
| 458.44 MiB |
+-----------------+
```
#### metrics
##### Description
Creates a union of the following information:
* performance_schema.global_status (information_schema.GLOBAL_STATUS in MySQL 5.6)
* information_schema.INNODB_METRICS
* Performance Schema global memory usage information (only in MySQL 5.7)
* Current time
In MySQL 5.7 it is required that performance_schema = ON, though there is no requirements to which
instruments and consumers that are enabled. See also the description of the Enabled column below.
For view has the following columns:
* Variable_name: The name of the variable
* Variable_value: The value of the variable
* Type: The type of the variable. This will depend on the source, e.g. Global Status, InnoDB Metrics - ..., etc.
* Enabled: Whether the variable is enabled or not. Possible values are 'YES', 'NO', 'PARTIAL'.
PARTIAL is currently only supported for the memory usage variables and means some but not all of the memory/% instruments are enabled.
##### Structures
```SQL
mysql> DESC metrics;
+----------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| Variable_name | varchar(193) | YES | | NULL | |
| Variable_value | text | YES | | NULL | |
| Type | varchar(210) | YES | | NULL | |
| Enabled | varchar(7) | NO | | | |
+----------------+--------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
mysq> DESC metrics_56;
+----------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| Variable_name | varchar(193) | YES | | NULL | |
| Variable_value | text | YES | | NULL | |
| Type | varchar(210) | YES | | NULL | |
| Enabled | varchar(7) | NO | | | |
+----------------+--------------+------+-----+---------+-------+
4 rows in set (0.01 sec)
```
##### Example
```SQL
mysql> SELECT * FROM metrics;
+-----------------------------------------------+-------------------------...+--------------------------------------+---------+
| Variable_name | Variable_value ...| Type | Enabled |
+-----------------------------------------------+-------------------------...+--------------------------------------+---------+
| aborted_clients | 0 ...| Global Status | YES |
| aborted_connects | 0 ...| Global Status | YES |
| binlog_cache_disk_use | 0 ...| Global Status | YES |
| binlog_cache_use | 0 ...| Global Status | YES |
| binlog_stmt_cache_disk_use | 0 ...| Global Status | YES |
| binlog_stmt_cache_use | 0 ...| Global Status | YES |
| bytes_received | 217081 ...| Global Status | YES |
| bytes_sent | 27257 ...| Global Status | YES |
...
| innodb_rwlock_x_os_waits | 0 ...| InnoDB Metrics - server | YES |
| innodb_rwlock_x_spin_rounds | 2723 ...| InnoDB Metrics - server | YES |
| innodb_rwlock_x_spin_waits | 1 ...| InnoDB Metrics - server | YES |
| trx_active_transactions | 0 ...| InnoDB Metrics - transaction | NO |
...
| trx_rseg_current_size | 0 ...| InnoDB Metrics - transaction | NO |
| trx_rseg_history_len | 4 ...| InnoDB Metrics - transaction | YES |
| trx_rw_commits | 0 ...| InnoDB Metrics - transaction | NO |
| trx_undo_slots_cached | 0 ...| InnoDB Metrics - transaction | NO |
| trx_undo_slots_used | 0 ...| InnoDB Metrics - transaction | NO |
| memory_current_allocated | 138244216 ...| Performance Schema | PARTIAL |
| memory_total_allocated | 138244216 ...| Performance Schema | PARTIAL |
| NOW() | 2015-05-31 13:27:50.382 ...| System Time | YES |
| UNIX_TIMESTAMP() | 1433042870.382 ...| System Time | YES |
+-----------------------------------------------+-------------------------...+--------------------------------------+---------+
412 rows in set (0.02 sec)
```
#### processlist / x$processlist
##### Description
A detailed non-blocking processlist view to replace [INFORMATION_SCHEMA. | SHOW FULL] PROCESSLIST.
Performs less locking than the legacy sources, whilst giving extra information.
The output includes both background threads and user connections by default. See also `session` / `x$session`
for a view that contains only user session information.
##### Structures (5.7)
```SQL
mysql> desc processlist;
+------------------------+------------------------------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+------------------------------------------+------+-----+---------+-------+
| thd_id | bigint(20) unsigned | NO | | NULL | |
| conn_id | bigint(20) unsigned | YES | | NULL | |
| user | varchar(128) | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| command | varchar(16) | YES | | NULL | |
| state | varchar(64) | YES | | NULL | |
| time | bigint(20) | YES | | NULL | |
| current_statement | longtext | YES | | NULL | |
| statement_latency | text | YES | | NULL | |
| progress | decimal(26,2) | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_examined | bigint(20) unsigned | YES | | NULL | |
| rows_sent | bigint(20) unsigned | YES | | NULL | |
| rows_affected | bigint(20) unsigned | YES | | NULL | |
| tmp_tables | bigint(20) unsigned | YES | | NULL | |
| tmp_disk_tables | bigint(20) unsigned | YES | | NULL | |
| full_scan | varchar(3) | NO | | | |
| last_statement | longtext | YES | | NULL | |
| last_statement_latency | text | YES | | NULL | |
| current_memory | text | YES | | NULL | |
| last_wait | varchar(128) | YES | | NULL | |
| last_wait_latency | text | YES | | NULL | |
| source | varchar(64) | YES | | NULL | |
| trx_latency | text | YES | | NULL | |
| trx_state | enum('ACTIVE','COMMITTED','ROLLED BACK') | YES | | NULL | |
| trx_autocommit | enum('YES','NO') | YES | | NULL | |
| pid | varchar(1024) | YES | | NULL | |
| program_name | varchar(1024) | YES | | NULL | |
+------------------------+------------------------------------------+------+-----+---------+-------+
28 rows in set (0.04 sec)
mysql> desc x$processlist;
+------------------------+------------------------------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+------------------------------------------+------+-----+---------+-------+
| thd_id | bigint(20) unsigned | NO | | NULL | |
| conn_id | bigint(20) unsigned | YES | | NULL | |
| user | varchar(128) | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| command | varchar(16) | YES | | NULL | |
| state | varchar(64) | YES | | NULL | |
| time | bigint(20) | YES | | NULL | |
| current_statement | longtext | YES | | NULL | |
| statement_latency | bigint(20) unsigned | YES | | NULL | |
| progress | decimal(26,2) | YES | | NULL | |
| lock_latency | bigint(20) unsigned | YES | | NULL | |
| rows_examined | bigint(20) unsigned | YES | | NULL | |
| rows_sent | bigint(20) unsigned | YES | | NULL | |
| rows_affected | bigint(20) unsigned | YES | | NULL | |
| tmp_tables | bigint(20) unsigned | YES | | NULL | |
| tmp_disk_tables | bigint(20) unsigned | YES | | NULL | |
| full_scan | varchar(3) | NO | | | |
| last_statement | longtext | YES | | NULL | |
| last_statement_latency | bigint(20) unsigned | YES | | NULL | |
| current_memory | decimal(41,0) | YES | | NULL | |
| last_wait | varchar(128) | YES | | NULL | |
| last_wait_latency | varchar(20) | YES | | NULL | |
| source | varchar(64) | YES | | NULL | |
| trx_latency | bigint(20) unsigned | YES | | NULL | |
| trx_state | enum('ACTIVE','COMMITTED','ROLLED BACK') | YES | | NULL | |
| trx_autocommit | enum('YES','NO') | YES | | NULL | |
| pid | varchar(1024) | YES | | NULL | |
| program_name | varchar(1024) | YES | | NULL | |
+------------------------+------------------------------------------+------+-----+---------+-------+
28 rows in set (0.01 sec)
```
##### Example
```SQL
mysql> select * from sys.processlist where conn_id is not null and command != 'daemon' and conn_id != connection_id()\G
*************************** 1. row ***************************
thd_id: 44524
conn_id: 44502
user: msandbox@localhost
db: test
command: Query
state: alter table (flush)
time: 18
current_statement: alter table t1 add column g int
statement_latency: 18.45 s
progress: 98.84
lock_latency: 265.43 ms
rows_examined: 0
rows_sent: 0
rows_affected: 0
tmp_tables: 0
tmp_disk_tables: 0
full_scan: NO
last_statement: NULL
last_statement_latency: NULL
current_memory: 664.06 KiB
last_wait: wait/io/file/innodb/innodb_data_file
last_wait_latency: 1.07 us
source: fil0fil.cc:5146
trx_latency: NULL
trx_state: NULL
trx_autocommit: NULL
pid: 4212
program_name: mysql
```
#### ps_check_lost_instrumentation
##### Description
Used to check whether Performance Schema is not able to monitor all runtime data - only returns variables that have lost instruments
##### Structure
```SQL
mysql> desc ps_check_lost_instrumentation;
+----------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+---------------+------+-----+---------+-------+
| variable_name | varchar(64) | NO | | | |
| variable_value | varchar(1024) | YES | | NULL | |
+----------------+---------------+------+-----+---------+-------+
2 rows in set (0.09 sec)
```
##### Example
```SQL
mysql> select * from ps_check_lost_instrumentation;
+----------------------------------------+----------------+
| variable_name | variable_value |
+----------------------------------------+----------------+
| Performance_schema_file_handles_lost | 101223 |
| Performance_schema_file_instances_lost | 1231 |
+----------------------------------------+----------------+
```
#### schema_auto_increment_columns
##### Description
Present current auto_increment usage/capacity in all tables.
##### Structures
```SQL
mysql> desc schema_auto_increment_columns;
+----------------------+------------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------+------------------------+------+-----+---------+-------+
| table_schema | varchar(64) | NO | | | |
| table_name | varchar(64) | NO | | | |
| column_name | varchar(64) | NO | | | |
| data_type | varchar(64) | NO | | | |
| column_type | longtext | NO | | NULL | |
| is_signed | int(1) | NO | | 0 | |
| is_unsigned | int(1) | NO | | 0 | |
| max_value | bigint(21) unsigned | YES | | NULL | |
| auto_increment | bigint(21) unsigned | YES | | NULL | |
| auto_increment_ratio | decimal(25,4) unsigned | YES | | NULL | |
+----------------------+------------------------+------+-----+---------+-------+
```
##### Example
```SQL
mysql> select * from schema_auto_increment_columns limit 5;
+-------------------+-------------------+-------------+-----------+-------------+-----------+-------------+---------------------+----------------+----------------------+
| table_schema | table_name | column_name | data_type | column_type | is_signed | is_unsigned | max_value | auto_increment | auto_increment_ratio |
+-------------------+-------------------+-------------+-----------+-------------+-----------+-------------+---------------------+----------------+----------------------+
| test | t1 | i | tinyint | tinyint(4) | 1 | 0 | 127 | 34 | 0.2677 |
| mem__advisor_text | template_meta | hib_id | int | int(11) | 1 | 0 | 2147483647 | 516 | 0.0000 |
| mem__advisors | advisor_schedules | schedule_id | int | int(11) | 1 | 0 | 2147483647 | 249 | 0.0000 |
| mem__advisors | app_identity_path | hib_id | int | int(11) | 1 | 0 | 2147483647 | 251 | 0.0000 |
| mem__bean_config | plists | id | bigint | bigint(20) | 1 | 0 | 9223372036854775807 | 1 | 0.0000 |
+-------------------+-------------------+-------------+-----------+-------------+-----------+-------------+---------------------+----------------+----------------------+
```
#### schema_index_statistics / x$schema_index_statistics
##### Description
Statistics around indexes.
Ordered by the total wait time descending - top indexes are most contended.
##### Structures
```SQL
mysql> desc schema_index_statistics;
+----------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+---------------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| index_name | varchar(64) | YES | | NULL | |
| rows_selected | bigint(20) unsigned | NO | | NULL | |
| select_latency | text | YES | | NULL | |
| rows_inserted | bigint(20) unsigned | NO | | NULL | |
| insert_latency | text | YES | | NULL | |
| rows_updated | bigint(20) unsigned | NO | | NULL | |
| update_latency | text | YES | | NULL | |
| rows_deleted | bigint(20) unsigned | NO | | NULL | |
| delete_latency | text | YES | | NULL | |
+----------------+---------------------+------+-----+---------+-------+
11 rows in set (0.17 sec)
mysql> desc x$schema_index_statistics;
+----------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+---------------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| index_name | varchar(64) | YES | | NULL | |
| rows_selected | bigint(20) unsigned | NO | | NULL | |
| select_latency | bigint(20) unsigned | NO | | NULL | |
| rows_inserted | bigint(20) unsigned | NO | | NULL | |
| insert_latency | bigint(20) unsigned | NO | | NULL | |
| rows_updated | bigint(20) unsigned | NO | | NULL | |
| update_latency | bigint(20) unsigned | NO | | NULL | |
| rows_deleted | bigint(20) unsigned | NO | | NULL | |
| delete_latency | bigint(20) unsigned | NO | | NULL | |
+----------------+---------------------+------+-----+---------+-------+
11 rows in set (0.42 sec)
```
##### Example
```SQL
mysql> select * from schema_index_statistics limit 5;
+------------------+-------------+------------+---------------+----------------+---------------+----------------+--------------+----------------+--------------+----------------+
| table_schema | table_name | index_name | rows_selected | select_latency | rows_inserted | insert_latency | rows_updated | update_latency | rows_deleted | delete_latency |
+------------------+-------------+------------+---------------+----------------+---------------+----------------+--------------+----------------+--------------+----------------+
| mem | mysqlserver | PRIMARY | 6208 | 108.27 ms | 0 | 0 ps | 5470 | 1.47 s | 0 | 0 ps |
| mem | innodb | PRIMARY | 4666 | 76.27 ms | 0 | 0 ps | 4454 | 571.47 ms | 0 | 0 ps |
| mem | connection | PRIMARY | 1064 | 20.98 ms | 0 | 0 ps | 1064 | 457.30 ms | 0 | 0 ps |
| mem | environment | PRIMARY | 5566 | 151.17 ms | 0 | 0 ps | 694 | 252.57 ms | 0 | 0 ps |
| mem | querycache | PRIMARY | 1698 | 27.99 ms | 0 | 0 ps | 1698 | 371.72 ms | 0 | 0 ps |
+------------------+-------------+------------+---------------+----------------+---------------+----------------+--------------+----------------+--------------+----------------+
```
#### schema_object_overview
##### Description
Shows an overview of the types of objects within each schema
Note: On instances with a large numbers of objects, this could take some time to execute, and may not be recommended.
##### Structure
```SQL
mysql> desc schema_object_overview;
+-------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+-------------+------+-----+---------+-------+
| db | varchar(64) | NO | | | |
| object_type | varchar(64) | NO | | | |
| count | bigint(21) | NO | | 0 | |
+-------------+-------------+------+-----+---------+-------+
3 rows in set (0.08 sec)
```
##### Example
```SQL
mysql> select * from schema_object_overview;
+--------------------+---------------+-------+
| db | object_type | count |
+--------------------+---------------+-------+
| information_schema | SYSTEM VIEW | 60 |
| mysql | BASE TABLE | 31 |
| mysql | INDEX (BTREE) | 69 |
| performance_schema | BASE TABLE | 76 |
| sys | BASE TABLE | 1 |
| sys | FUNCTION | 12 |
| sys | INDEX (BTREE) | 1 |
| sys | PROCEDURE | 22 |
| sys | TRIGGER | 2 |
| sys | VIEW | 91 |
+--------------------+---------------+-------+
10 rows in set (1.58 sec)
```
#### schema_table_statistics / x$schema_table_statistics
##### Description
Statistics around tables.
Ordered by the total wait time descending - top tables are most contended.
Also includes the helper view (used by schema_table_statistics_with_buffer as well):
* x$ps_schema_table_statistics_io
##### Structures
```SQL
mysql> desc schema_table_statistics;
+-------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| total_latency | text | YES | | NULL | |
| rows_fetched | bigint(20) unsigned | NO | | NULL | |
| fetch_latency | text | YES | | NULL | |
| rows_inserted | bigint(20) unsigned | NO | | NULL | |
| insert_latency | text | YES | | NULL | |
| rows_updated | bigint(20) unsigned | NO | | NULL | |
| update_latency | text | YES | | NULL | |
| rows_deleted | bigint(20) unsigned | NO | | NULL | |
| delete_latency | text | YES | | NULL | |
| io_read_requests | decimal(42,0) | YES | | NULL | |
| io_read | text | YES | | NULL | |
| io_read_latency | text | YES | | NULL | |
| io_write_requests | decimal(42,0) | YES | | NULL | |
| io_write | text | YES | | NULL | |
| io_write_latency | text | YES | | NULL | |
| io_misc_requests | decimal(42,0) | YES | | NULL | |
| io_misc_latency | text | YES | | NULL | |
+-------------------+---------------------+------+-----+---------+-------+
19 rows in set (0.12 sec)
mysql> desc x$schema_table_statistics;
+-------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| rows_fetched | bigint(20) unsigned | NO | | NULL | |
| fetch_latency | bigint(20) unsigned | NO | | NULL | |
| rows_inserted | bigint(20) unsigned | NO | | NULL | |
| insert_latency | bigint(20) unsigned | NO | | NULL | |
| rows_updated | bigint(20) unsigned | NO | | NULL | |
| update_latency | bigint(20) unsigned | NO | | NULL | |
| rows_deleted | bigint(20) unsigned | NO | | NULL | |
| delete_latency | bigint(20) unsigned | NO | | NULL | |
| io_read_requests | decimal(42,0) | YES | | NULL | |
| io_read | decimal(41,0) | YES | | NULL | |
| io_read_latency | decimal(42,0) | YES | | NULL | |
| io_write_requests | decimal(42,0) | YES | | NULL | |
| io_write | decimal(41,0) | YES | | NULL | |
| io_write_latency | decimal(42,0) | YES | | NULL | |
| io_misc_requests | decimal(42,0) | YES | | NULL | |
| io_misc_latency | decimal(42,0) | YES | | NULL | |
+-------------------+---------------------+------+-----+---------+-------+
19 rows in set (0.13 sec)
mysql> desc x$ps_schema_table_statistics_io;
+---------------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------------------+---------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| count_read | decimal(42,0) | YES | | NULL | |
| sum_number_of_bytes_read | decimal(41,0) | YES | | NULL | |
| sum_timer_read | decimal(42,0) | YES | | NULL | |
| count_write | decimal(42,0) | YES | | NULL | |
| sum_number_of_bytes_write | decimal(41,0) | YES | | NULL | |
| sum_timer_write | decimal(42,0) | YES | | NULL | |
| count_misc | decimal(42,0) | YES | | NULL | |
| sum_timer_misc | decimal(42,0) | YES | | NULL | |
+---------------------------+---------------+------+-----+---------+-------+
10 rows in set (0.10 sec)
```
##### Example
```SQL
mysql> select * from schema_table_statistics\G
*************************** 1. row ***************************
table_schema: sys
table_name: sys_config
total_latency: 0 ps
rows_fetched: 0
fetch_latency: 0 ps
rows_inserted: 0
insert_latency: 0 ps
rows_updated: 0
update_latency: 0 ps
rows_deleted: 0
delete_latency: 0 ps
io_read_requests: 8
io_read: 2.28 KiB
io_read_latency: 727.32 us
io_write_requests: 0
io_write: 0 bytes
io_write_latency: 0 ps
io_misc_requests: 10
io_misc_latency: 126.88 us
```
#### schema_redundant_indexes / x$schema_flattened_keys
##### Description
Shows indexes which are made redundant (or duplicate) by other (dominant) keys.
Also includes the the helper view `x$schema_flattened_keys`.
##### Structures
```SQL
mysql> desc sys.schema_redundant_indexes;
+----------------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------------+--------------+------+-----+---------+-------+
| table_schema | varchar(64) | NO | | | |
| table_name | varchar(64) | NO | | | |
| redundant_index_name | varchar(64) | NO | | | |
| redundant_index_columns | text | YES | | NULL | |
| redundant_index_non_unique | bigint(1) | YES | | NULL | |
| dominant_index_name | varchar(64) | NO | | | |
| dominant_index_columns | text | YES | | NULL | |
| dominant_index_non_unique | bigint(1) | YES | | NULL | |
| subpart_exists | int(1) | NO | | 0 | |
| sql_drop_index | varchar(223) | YES | | NULL | |
+----------------------------+--------------+------+-----+---------+-------+
10 rows in set (0.00 sec)
mysql> desc sys.x$schema_flattened_keys;
+----------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+-------------+------+-----+---------+-------+
| table_schema | varchar(64) | NO | | | |
| table_name | varchar(64) | NO | | | |
| index_name | varchar(64) | NO | | | |
| non_unique | bigint(1) | YES | | NULL | |
| subpart_exists | bigint(1) | YES | | NULL | |
| index_columns | text | YES | | NULL | |
+----------------+-------------+------+-----+---------+-------+
6 rows in set (0.00 sec)
```
##### Example
```SQL
mysql> select * from sys.schema_redundant_indexes\G
*************************** 1. row ***************************
table_schema: test
table_name: rkey
redundant_index_name: j
redundant_index_columns: j
redundant_index_non_unique: 1
dominant_index_name: j_2
dominant_index_columns: j,k
dominant_index_non_unique: 1
subpart_exists: 0
sql_drop_index: ALTER TABLE `test`.`rkey` DROP INDEX `j`
1 row in set (0.20 sec)
mysql> SHOW CREATE TABLE test.rkey\G
*************************** 1. row ***************************
Table: rkey
Create Table: CREATE TABLE `rkey` (
`i` int(11) NOT NULL,
`j` int(11) DEFAULT NULL,
`k` int(11) DEFAULT NULL,
PRIMARY KEY (`i`),
KEY `j` (`j`),
KEY `j_2` (`j`,`k`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.06 sec)
```
#### schema_table_lock_waits / x$schema_table_lock_waits
##### Description
Shows sessions that are blocked waiting on table metadata locks, and who is blocking them.
##### Structures
```SQL
mysql> desc schema_table_lock_waits;
+------------------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------------+---------------------+------+-----+---------+-------+
| object_schema | varchar(64) | YES | | NULL | |
| object_name | varchar(64) | YES | | NULL | |
| waiting_thread_id | bigint(20) unsigned | NO | | NULL | |
| waiting_pid | bigint(20) unsigned | YES | | NULL | |
| waiting_account | text | YES | | NULL | |
| waiting_lock_type | varchar(32) | NO | | NULL | |
| waiting_lock_duration | varchar(32) | NO | | NULL | |
| waiting_query | longtext | YES | | NULL | |
| waiting_query_secs | bigint(20) | YES | | NULL | |
| waiting_query_rows_affected | bigint(20) unsigned | YES | | NULL | |
| waiting_query_rows_examined | bigint(20) unsigned | YES | | NULL | |
| blocking_thread_id | bigint(20) unsigned | NO | | NULL | |
| blocking_pid | bigint(20) unsigned | YES | | NULL | |
| blocking_account | text | YES | | NULL | |
| blocking_lock_type | varchar(32) | NO | | NULL | |
| blocking_lock_duration | varchar(32) | NO | | NULL | |
| sql_kill_blocking_query | varchar(31) | YES | | NULL | |
| sql_kill_blocking_connection | varchar(25) | YES | | NULL | |
+------------------------------+---------------------+------+-----+---------+-------+
18 rows in set (0.15 sec)
mysql> desc x$schema_table_lock_waits;
+------------------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------------+---------------------+------+-----+---------+-------+
| object_schema | varchar(64) | YES | | NULL | |
| object_name | varchar(64) | YES | | NULL | |
| waiting_thread_id | bigint(20) unsigned | NO | | NULL | |
| waiting_pid | bigint(20) unsigned | YES | | NULL | |
| waiting_account | text | YES | | NULL | |
| waiting_lock_type | varchar(32) | NO | | NULL | |
| waiting_lock_duration | varchar(32) | NO | | NULL | |
| waiting_query | longtext | YES | | NULL | |
| waiting_query_secs | bigint(20) | YES | | NULL | |
| waiting_query_rows_affected | bigint(20) unsigned | YES | | NULL | |
| waiting_query_rows_examined | bigint(20) unsigned | YES | | NULL | |
| blocking_thread_id | bigint(20) unsigned | NO | | NULL | |
| blocking_pid | bigint(20) unsigned | YES | | NULL | |
| blocking_account | text | YES | | NULL | |
| blocking_lock_type | varchar(32) | NO | | NULL | |
| blocking_lock_duration | varchar(32) | NO | | NULL | |
| sql_kill_blocking_query | varchar(31) | YES | | NULL | |
| sql_kill_blocking_connection | varchar(25) | YES | | NULL | |
+------------------------------+---------------------+------+-----+---------+-------+
18 rows in set (0.03 sec)
```
##### Example
```SQL
mysql> select * from sys.schema_table_lock_waits\G
*************************** 1. row ***************************
object_schema: test
object_name: t
waiting_thread_id: 43
waiting_pid: 21
waiting_account: msandbox@localhost
waiting_lock_type: SHARED_UPGRADABLE
waiting_lock_duration: TRANSACTION
waiting_query: alter table test.t add foo int
waiting_query_secs: 988
waiting_query_rows_affected: 0
waiting_query_rows_examined: 0
blocking_thread_id: 42
blocking_pid: 20
blocking_account: msandbox@localhost
blocking_lock_type: SHARED_NO_READ_WRITE
blocking_lock_duration: TRANSACTION
sql_kill_blocking_query: KILL QUERY 20
sql_kill_blocking_connection: KILL 20
```
#### schema_table_statistics_with_buffer / x$schema_table_statistics_with_buffer
##### Description
Statistics around tables.
Ordered by the total wait time descending - top tables are most contended.
More statistics such as caching stats for the InnoDB buffer pool with InnoDB tables
Uses the x$ps_schema_table_statistics_io helper view from schema_table_statistics.
##### Structures
```SQL
mysql> desc schema_table_statistics_with_buffer;
+----------------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------------+---------------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| rows_fetched | bigint(20) unsigned | NO | | NULL | |
| fetch_latency | text | YES | | NULL | |
| rows_inserted | bigint(20) unsigned | NO | | NULL | |
| insert_latency | text | YES | | NULL | |
| rows_updated | bigint(20) unsigned | NO | | NULL | |
| update_latency | text | YES | | NULL | |
| rows_deleted | bigint(20) unsigned | NO | | NULL | |
| delete_latency | text | YES | | NULL | |
| io_read_requests | decimal(42,0) | YES | | NULL | |
| io_read | text | YES | | NULL | |
| io_read_latency | text | YES | | NULL | |
| io_write_requests | decimal(42,0) | YES | | NULL | |
| io_write | text | YES | | NULL | |
| io_write_latency | text | YES | | NULL | |
| io_misc_requests | decimal(42,0) | YES | | NULL | |
| io_misc_latency | text | YES | | NULL | |
| innodb_buffer_allocated | text | YES | | NULL | |
| innodb_buffer_data | text | YES | | NULL | |
| innodb_buffer_free | text | YES | | NULL | |
| innodb_buffer_pages | bigint(21) | YES | | 0 | |
| innodb_buffer_pages_hashed | bigint(21) | YES | | 0 | |
| innodb_buffer_pages_old | bigint(21) | YES | | 0 | |
| innodb_buffer_rows_cached | decimal(44,0) | YES | | 0 | |
+----------------------------+---------------------+------+-----+---------+-------+
25 rows in set (0.05 sec)
mysql> desc x$schema_table_statistics_with_buffer;
+----------------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------------+---------------------+------+-----+---------+-------+
| table_schema | varchar(64) | YES | | NULL | |
| table_name | varchar(64) | YES | | NULL | |
| rows_fetched | bigint(20) unsigned | NO | | NULL | |
| fetch_latency | bigint(20) unsigned | NO | | NULL | |
| rows_inserted | bigint(20) unsigned | NO | | NULL | |
| insert_latency | bigint(20) unsigned | NO | | NULL | |
| rows_updated | bigint(20) unsigned | NO | | NULL | |
| update_latency | bigint(20) unsigned | NO | | NULL | |
| rows_deleted | bigint(20) unsigned | NO | | NULL | |
| delete_latency | bigint(20) unsigned | NO | | NULL | |
| io_read_requests | decimal(42,0) | YES | | NULL | |
| io_read | decimal(41,0) | YES | | NULL | |
| io_read_latency | decimal(42,0) | YES | | NULL | |
| io_write_requests | decimal(42,0) | YES | | NULL | |
| io_write | decimal(41,0) | YES | | NULL | |
| io_write_latency | decimal(42,0) | YES | | NULL | |
| io_misc_requests | decimal(42,0) | YES | | NULL | |
| io_misc_latency | decimal(42,0) | YES | | NULL | |
| innodb_buffer_allocated | decimal(43,0) | YES | | NULL | |
| innodb_buffer_data | decimal(43,0) | YES | | NULL | |
| innodb_buffer_free | decimal(44,0) | YES | | NULL | |
| innodb_buffer_pages | bigint(21) | YES | | 0 | |
| innodb_buffer_pages_hashed | bigint(21) | YES | | 0 | |
| innodb_buffer_pages_old | bigint(21) | YES | | 0 | |
| innodb_buffer_rows_cached | decimal(44,0) | YES | | 0 | |
+----------------------------+---------------------+------+-----+---------+-------+
25 rows in set (0.17 sec)
```
##### Example
```SQL
mysql> select * from schema_table_statistics_with_buffer limit 1\G
*************************** 1. row ***************************
table_schema: mem
table_name: mysqlserver
rows_fetched: 27087
fetch_latency: 442.72 ms
rows_inserted: 2
insert_latency: 185.04 us
rows_updated: 5096
update_latency: 1.39 s
rows_deleted: 0
delete_latency: 0 ps
io_read_requests: 2565
io_read_bytes: 1121627
io_read_latency: 10.07 ms
io_write_requests: 1691
io_write_bytes: 128383
io_write_latency: 14.17 ms
io_misc_requests: 2698
io_misc_latency: 433.66 ms
innodb_buffer_pages: 19
innodb_buffer_pages_hashed: 19
innodb_buffer_pages_old: 19
innodb_buffer_bytes_allocated: 311296
innodb_buffer_bytes_data: 1924
innodb_buffer_rows_cached: 2
```
#### schema_tables_with_full_table_scans / x$schema_tables_with_full_table_scans
##### Description
Finds tables that are being accessed by full table scans ordering by the number of rows scanned descending.
##### Structures
```SQL
mysql> desc schema_tables_with_full_table_scans;
+-------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------+-------+
| object_schema | varchar(64) | YES | | NULL | |
| object_name | varchar(64) | YES | | NULL | |
| rows_full_scanned | bigint(20) unsigned | NO | | NULL | |
| latency | text | YES | | NULL | |
+-------------------+---------------------+------+-----+---------+-------+
4 rows in set (0.02 sec)
mysql> desc x$schema_tables_with_full_table_scans;
+-------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------+-------+
| object_schema | varchar(64) | YES | | NULL | |
| object_name | varchar(64) | YES | | NULL | |
| rows_full_scanned | bigint(20) unsigned | NO | | NULL | |
| latency | bigint(20) unsigned | NO | | NULL | |
+-------------------+---------------------+------+-----+---------+-------+
4 rows in set (0.03 sec)
```
##### Example
```SQL
mysql> select * from schema_tables_with_full_table_scans limit 5;
+--------------------+--------------------------------+-------------------+-----------+
| object_schema | object_name | rows_full_scanned | latency |
+--------------------+--------------------------------+-------------------+-----------+
| mem30__instruments | fsstatistics | 10207042 | 13.10 s |
| mem30__instruments | preparedstatementapidata | 436428 | 973.27 ms |
| mem30__instruments | mysqlprocessactivity | 411702 | 282.07 ms |
| mem30__instruments | querycachequeriesincachedata | 374011 | 767.15 ms |
| mem30__instruments | rowaccessesdata | 322321 | 1.55 s |
+--------------------+--------------------------------+-------------------+-----------+
```
#### schema_unused_indexes
##### Description
Finds indexes that have had no events against them (and hence, no usage).
To trust whether the data from this view is representative of your workload, you should ensure that the server has been up for a representative amount of time before using it.
PRIMARY (key) indexes are ignored.
##### Structure
```SQL
mysql> desc schema_unused_indexes;
+---------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+-------------+------+-----+---------+-------+
| object_schema | varchar(64) | YES | | NULL | |
| object_name | varchar(64) | YES | | NULL | |
| index_name | varchar(64) | YES | | NULL | |
+---------------+-------------+------+-----+---------+-------+
3 rows in set (0.09 sec)
```
##### Example
```SQL
mysql> select * from schema_unused_indexes limit 5;
+--------------------+---------------------+--------------------+
| object_schema | object_name | index_name |
+--------------------+---------------------+--------------------+
| mem30__bean_config | plists | path |
| mem30__config | group_selections | name |
| mem30__config | notification_groups | name |
| mem30__config | user_form_defaults | FKC1AEF1F9E7EE2CFB |
| mem30__enterprise | whats_new_entries | entryId |
+--------------------+---------------------+--------------------+
```
#### session / x$session
##### Description
A detailed non-blocking processlist view to replace [INFORMATION_SCHEMA. | SHOW FULL] PROCESSLIST.
Performs less locking than the legacy sources, whilst giving extra information.
The output of this view is restricted to threads from user sessions. See also processlist / x$processlist which contains both user and background threads.
##### Structures (5.7)
```SQL
mysql> desc session;
+------------------------+------------------------------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+------------------------------------------+------+-----+---------+-------+
| thd_id | bigint(20) unsigned | NO | | NULL | |
| conn_id | bigint(20) unsigned | YES | | NULL | |
| user | varchar(128) | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| command | varchar(16) | YES | | NULL | |
| state | varchar(64) | YES | | NULL | |
| time | bigint(20) | YES | | NULL | |
| current_statement | longtext | YES | | NULL | |
| statement_latency | text | YES | | NULL | |
| progress | decimal(26,2) | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_examined | bigint(20) unsigned | YES | | NULL | |
| rows_sent | bigint(20) unsigned | YES | | NULL | |
| rows_affected | bigint(20) unsigned | YES | | NULL | |
| tmp_tables | bigint(20) unsigned | YES | | NULL | |
| tmp_disk_tables | bigint(20) unsigned | YES | | NULL | |
| full_scan | varchar(3) | NO | | | |
| last_statement | longtext | YES | | NULL | |
| last_statement_latency | text | YES | | NULL | |
| current_memory | text | YES | | NULL | |
| last_wait | varchar(128) | YES | | NULL | |
| last_wait_latency | text | YES | | NULL | |
| source | varchar(64) | YES | | NULL | |
| trx_latency | text | YES | | NULL | |
| trx_state | enum('ACTIVE','COMMITTED','ROLLED BACK') | YES | | NULL | |
| trx_autocommit | enum('YES','NO') | YES | | NULL | |
| pid | varchar(1024) | YES | | NULL | |
| program_name | varchar(1024) | YES | | NULL | |
+------------------------+------------------------------------------+------+-----+---------+-------+
28 rows in set (0.00 sec)
mysql> desc x$session;
+------------------------+------------------------------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+------------------------------------------+------+-----+---------+-------+
| thd_id | bigint(20) unsigned | NO | | NULL | |
| conn_id | bigint(20) unsigned | YES | | NULL | |
| user | varchar(128) | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| command | varchar(16) | YES | | NULL | |
| state | varchar(64) | YES | | NULL | |
| time | bigint(20) | YES | | NULL | |
| current_statement | longtext | YES | | NULL | |
| statement_latency | bigint(20) unsigned | YES | | NULL | |
| progress | decimal(26,2) | YES | | NULL | |
| lock_latency | bigint(20) unsigned | YES | | NULL | |
| rows_examined | bigint(20) unsigned | YES | | NULL | |
| rows_sent | bigint(20) unsigned | YES | | NULL | |
| rows_affected | bigint(20) unsigned | YES | | NULL | |
| tmp_tables | bigint(20) unsigned | YES | | NULL | |
| tmp_disk_tables | bigint(20) unsigned | YES | | NULL | |
| full_scan | varchar(3) | NO | | | |
| last_statement | longtext | YES | | NULL | |
| last_statement_latency | bigint(20) unsigned | YES | | NULL | |
| current_memory | decimal(41,0) | YES | | NULL | |
| last_wait | varchar(128) | YES | | NULL | |
| last_wait_latency | varchar(20) | YES | | NULL | |
| source | varchar(64) | YES | | NULL | |
| trx_latency | bigint(20) unsigned | YES | | NULL | |
| trx_state | enum('ACTIVE','COMMITTED','ROLLED BACK') | YES | | NULL | |
| trx_autocommit | enum('YES','NO') | YES | | NULL | |
| pid | varchar(1024) | YES | | NULL | |
| program_name | varchar(1024) | YES | | NULL | |
+------------------------+------------------------------------------+------+-----+---------+-------+
28 rows in set (0.00 sec)
```
##### Example
```SQL
mysql> select * from sys.session\G
*************************** 1. row ***************************
thd_id: 24
conn_id: 2
user: root@localhost
db: sys
command: Query
state: Sending data
time: 0
current_statement: select * from sys.session
statement_latency: 137.22 ms
progress: NULL
lock_latency: 33.75 ms
rows_examined: 0
rows_sent: 0
rows_affected: 0
tmp_tables: 4
tmp_disk_tables: 1
full_scan: YES
last_statement: NULL
last_statement_latency: NULL
current_memory: 3.26 MiB
last_wait: wait/synch/mutex/innodb/file_format_max_mutex
last_wait_latency: 64.09 ns
source: trx0sys.cc:778
trx_latency: 7.88 s
trx_state: ACTIVE
trx_autocommit: NO
pid: 4212
program_name: mysql
```
#### session_ssl_status
##### Description
Shows SSL version, cipher and the count of re-used SSL sessions per connection
##### Structures
```SQL
mysql> desc sys.session_ssl_status;
+---------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------------+---------------------+------+-----+---------+-------+
| thread_id | bigint(20) unsigned | NO | | NULL | |
| ssl_version | varchar(1024) | YES | | NULL | |
| ssl_cipher | varchar(1024) | YES | | NULL | |
| ssl_sessions_reused | varchar(1024) | YES | | NULL | |
+---------------------+---------------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
```
##### Example
```SQL
mysql> select * from session_ssl_status;
+-----------+-------------+--------------------+---------------------+
| thread_id | ssl_version | ssl_cipher | ssl_sessions_reused |
+-----------+-------------+--------------------+---------------------+
| 26 | TLSv1 | DHE-RSA-AES256-SHA | 0 |
| 27 | TLSv1 | DHE-RSA-AES256-SHA | 0 |
| 28 | TLSv1 | DHE-RSA-AES256-SHA | 0 |
+-----------+-------------+--------------------+---------------------+
3 rows in set (0.00 sec)
```
#### statement_analysis / x$statement_analysis
##### Description
Lists a normalized statement view with aggregated statistics, mimics the MySQL Enterprise Monitor Query Analysis view, ordered by the total execution time per normalized statement
##### Structures
```SQL
mysql> desc statement_analysis;
+-------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| full_scan | varchar(1) | NO | | | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| err_count | bigint(20) unsigned | NO | | NULL | |
| warn_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_sent_avg | decimal(21,0) | NO | | 0 | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_examined_avg | decimal(21,0) | NO | | 0 | |
| rows_affected | bigint(20) unsigned | NO | | NULL | |
| rows_affected_avg | decimal(21,0) | NO | | 0 | |
| tmp_tables | bigint(20) unsigned | NO | | NULL | |
| tmp_disk_tables | bigint(20) unsigned | NO | | NULL | |
| rows_sorted | bigint(20) unsigned | NO | | NULL | |
| sort_merge_passes | bigint(20) unsigned | NO | | NULL | |
| digest | varchar(32) | YES | | NULL | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
+-------------------+---------------------+------+-----+---------------------+-------+
23 rows in set (0.26 sec)
mysql> desc x$statement_analysis;
+-------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| full_scan | varchar(1) | NO | | | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| err_count | bigint(20) unsigned | NO | | NULL | |
| warn_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| lock_latency | bigint(20) unsigned | NO | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_sent_avg | decimal(21,0) | NO | | 0 | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_examined_avg | decimal(21,0) | NO | | 0 | |
| rows_affected | bigint(20) unsigned | NO | | NULL | |
| rows_affected_avg | decimal(21,0) | NO | | 0 | |
| tmp_tables | bigint(20) unsigned | NO | | NULL | |
| tmp_disk_tables | bigint(20) unsigned | NO | | NULL | |
| rows_sorted | bigint(20) unsigned | NO | | NULL | |
| sort_merge_passes | bigint(20) unsigned | NO | | NULL | |
| digest | varchar(32) | YES | | NULL | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
+-------------------+---------------------+------+-----+---------------------+-------+
23 rows in set (0.27 sec)
```
##### Example
```SQL
mysql> select * from statement_analysis limit 1\G
*************************** 1. row ***************************
query: SELECT * FROM `schema_object_o ... MA` , `information_schema` ...
db: sys
full_scan: *
exec_count: 2
err_count: 0
warn_count: 0
total_latency: 16.75 s
max_latency: 16.57 s
avg_latency: 8.38 s
lock_latency: 16.69 s
rows_sent: 84
rows_sent_avg: 42
rows_examined: 20012
rows_examined_avg: 10006
rows_affected: 0
rows_affected_avg: 0
tmp_tables: 378
tmp_disk_tables: 66
rows_sorted: 168
sort_merge_passes: 0
digest: 54f9bd520f0bbf15db0c2ed93386bec9
first_seen: 2014-03-07 13:13:41
last_seen: 2014-03-07 13:13:48
```
#### statements_with_errors_or_warnings / x$statements_with_errors_or_warnings
##### Description
Lists all normalized statements that have raised errors or warnings.
##### Structures
```SQL
mysql> desc statements_with_errors_or_warnings;
+-------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| errors | bigint(20) unsigned | NO | | NULL | |
| error_pct | decimal(27,4) | NO | | 0.0000 | |
| warnings | bigint(20) unsigned | NO | | NULL | |
| warning_pct | decimal(27,4) | NO | | 0.0000 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+-------------+---------------------+------+-----+---------------------+-------+
10 rows in set (0.55 sec)
mysql> desc x$statements_with_errors_or_warnings;
+-------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| errors | bigint(20) unsigned | NO | | NULL | |
| error_pct | decimal(27,4) | NO | | 0.0000 | |
| warnings | bigint(20) unsigned | NO | | NULL | |
| warning_pct | decimal(27,4) | NO | | 0.0000 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+-------------+---------------------+------+-----+---------------------+-------+
10 rows in set (0.25 sec)
```
##### Example
```SQL
mysql> select * from statements_with_errors_or_warnings LIMIT 1\G
*************************** 1. row ***************************
query: CREATE OR REPLACE ALGORITHM = ... _delete` AS `rows_deleted` ...
db: sys
exec_count: 2
errors: 1
error_pct: 50.0000
warnings: 0
warning_pct: 0.0000
first_seen: 2014-03-07 12:56:54
last_seen: 2014-03-07 13:01:01
digest: 943a788859e623d5f7798ba0ae0fd8a9
```
#### statements_with_full_table_scans / x$statements_with_full_table_scans
##### Description
Lists all normalized statements that use have done a full table scan ordered by number the percentage of times a full scan was done, then by the statement latency.
This view ignores SHOW statements, as these always cause a full table scan, and there is nothing that can be done about this.
##### Structures
```SQL
mysql> desc statements_with_full_table_scans;
+--------------------------+------------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------------+------------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| no_index_used_count | bigint(20) unsigned | NO | | NULL | |
| no_good_index_used_count | bigint(20) unsigned | NO | | NULL | |
| no_index_used_pct | decimal(24,0) | NO | | 0 | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_sent_avg | decimal(21,0) unsigned | YES | | NULL | |
| rows_examined_avg | decimal(21,0) unsigned | YES | | NULL | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+--------------------------+------------------------+------+-----+---------------------+-------+
14 rows in set (0.04 sec)
mysql> desc x$statements_with_full_table_scans;
+--------------------------+------------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------------+------------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| no_index_used_count | bigint(20) unsigned | NO | | NULL | |
| no_good_index_used_count | bigint(20) unsigned | NO | | NULL | |
| no_index_used_pct | decimal(24,0) | NO | | 0 | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_sent_avg | decimal(21,0) unsigned | YES | | NULL | |
| rows_examined_avg | decimal(21,0) unsigned | YES | | NULL | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+--------------------------+------------------------+------+-----+---------------------+-------+
14 rows in set (0.14 sec)
```
##### Example
```SQL
mysql> select * from statements_with_full_table_scans limit 1\G
*************************** 1. row ***************************
query: SELECT * FROM `schema_tables_w ... ex_usage` . `COUNT_READ` DESC
db: sys
exec_count: 1
total_latency: 88.20 ms
no_index_used_count: 1
no_good_index_used_count: 0
no_index_used_pct: 100
rows_sent: 0
rows_examined: 1501
rows_sent_avg: 0
rows_examined_avg: 1501
first_seen: 2014-03-07 13:58:20
last_seen: 2014-03-07 13:58:20
digest: 64baecd5c1e1e1651a6b92e55442a288
```
#### statements_with_runtimes_in_95th_percentile / x$statements_with_runtimes_in_95th_percentile
##### Description
Lists all statements whose average runtime, in microseconds, is in the top 95th percentile.
Also includes two helper views:
* x$ps_digest_avg_latency_distribution
* x$ps_digest_95th_percentile_by_avg_us
##### Structures
```SQL
mysql> desc statements_with_runtimes_in_95th_percentile;
+-------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| full_scan | varchar(1) | NO | | | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| err_count | bigint(20) unsigned | NO | | NULL | |
| warn_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_sent_avg | decimal(21,0) | NO | | 0 | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_examined_avg | decimal(21,0) | NO | | 0 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+-------------------+---------------------+------+-----+---------------------+-------+
16 rows in set (0.11 sec)
mysql> desc x$statements_with_runtimes_in_95th_percentile;
+-------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| full_scan | varchar(1) | NO | | | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| err_count | bigint(20) unsigned | NO | | NULL | |
| warn_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_sent_avg | decimal(21,0) | NO | | 0 | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_examined_avg | decimal(21,0) | NO | | 0 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+-------------------+---------------------+------+-----+---------------------+-------+
16 rows in set (0.00 sec)
mysql> desc x$ps_digest_avg_latency_distribution;
+--------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------+---------------+------+-----+---------+-------+
| cnt | bigint(21) | NO | | 0 | |
| avg_us | decimal(21,0) | YES | | NULL | |
+--------+---------------+------+-----+---------+-------+
2 rows in set (0.10 sec)
mysql> desc x$ps_digest_95th_percentile_by_avg_us;
+------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| avg_us | decimal(21,0) | YES | | NULL | |
| percentile | decimal(46,4) | NO | | 0.0000 | |
+------------+---------------+------+-----+---------+-------+
2 rows in set (0.15 sec)
```
##### Example
```SQL
mysql> select * from statements_with_runtimes_in_95th_percentile\G
*************************** 1. row ***************************
query: SELECT * FROM `schema_object_o ... MA` , `information_schema` ...
db: sys
full_scan: *
exec_count: 2
err_count: 0
warn_count: 0
total_latency: 16.75 s
max_latency: 16.57 s
avg_latency: 8.38 s
rows_sent: 84
rows_sent_avg: 42
rows_examined: 20012
rows_examined_avg: 10006
first_seen: 2014-03-07 13:13:41
last_seen: 2014-03-07 13:13:48
digest: 54f9bd520f0bbf15db0c2ed93386bec9
```
#### statements_with_sorting / x$statements_with_sorting
##### Description
Lists all normalized statements that have done sorts, ordered by total_latency descending.
##### Structures
```SQL
mysql> desc statements_with_sorting;
+-------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| sort_merge_passes | bigint(20) unsigned | NO | | NULL | |
| avg_sort_merges | decimal(21,0) | NO | | 0 | |
| sorts_using_scans | bigint(20) unsigned | NO | | NULL | |
| sort_using_range | bigint(20) unsigned | NO | | NULL | |
| rows_sorted | bigint(20) unsigned | NO | | NULL | |
| avg_rows_sorted | decimal(21,0) | NO | | 0 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+-------------------+---------------------+------+-----+---------------------+-------+
13 rows in set (0.01 sec)
mysql> desc x$statements_with_sorting;
+-------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| sort_merge_passes | bigint(20) unsigned | NO | | NULL | |
| avg_sort_merges | decimal(21,0) | NO | | 0 | |
| sorts_using_scans | bigint(20) unsigned | NO | | NULL | |
| sort_using_range | bigint(20) unsigned | NO | | NULL | |
| rows_sorted | bigint(20) unsigned | NO | | NULL | |
| avg_rows_sorted | decimal(21,0) | NO | | 0 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+-------------------+---------------------+------+-----+---------------------+-------+
13 rows in set (0.04 sec)
```
##### Example
```SQL
mysql> select * from statements_with_sorting limit 1\G
*************************** 1. row ***************************
query: SELECT * FROM `schema_object_o ... MA` , `information_schema` ...
db: sys
exec_count: 2
total_latency: 16.75 s
sort_merge_passes: 0
avg_sort_merges: 0
sorts_using_scans: 12
sort_using_range: 0
rows_sorted: 168
avg_rows_sorted: 84
first_seen: 2014-03-07 13:13:41
last_seen: 2014-03-07 13:13:48
digest: 54f9bd520f0bbf15db0c2ed93386bec9
```
#### statements_with_temp_tables / x$statements_with_temp_tables
##### Description
Lists all normalized statements that use temporary tables ordered by number of on disk temporary tables descending first, then by the number of memory tables.
##### Structures
```SQL
mysql> desc statements_with_temp_tables;
+--------------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| memory_tmp_tables | bigint(20) unsigned | NO | | NULL | |
| disk_tmp_tables | bigint(20) unsigned | NO | | NULL | |
| avg_tmp_tables_per_query | decimal(21,0) | NO | | 0 | |
| tmp_tables_to_disk_pct | decimal(24,0) | NO | | 0 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+--------------------------+---------------------+------+-----+---------------------+-------+
11 rows in set (0.30 sec)
mysql> desc x$statements_with_temp_tables;
+--------------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------------+---------------------+------+-----+---------------------+-------+
| query | longtext | YES | | NULL | |
| db | varchar(64) | YES | | NULL | |
| exec_count | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| memory_tmp_tables | bigint(20) unsigned | NO | | NULL | |
| disk_tmp_tables | bigint(20) unsigned | NO | | NULL | |
| avg_tmp_tables_per_query | decimal(21,0) | NO | | 0 | |
| tmp_tables_to_disk_pct | decimal(24,0) | NO | | 0 | |
| first_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| last_seen | timestamp | NO | | 0000-00-00 00:00:00 | |
| digest | varchar(32) | YES | | NULL | |
+--------------------------+---------------------+------+-----+---------------------+-------+
11 rows in set (0.05 sec)
```
##### Example
```SQL
mysql> select * from statements_with_temp_tables limit 1\G
*************************** 1. row ***************************
query: SELECT * FROM `schema_object_o ... MA` , `information_schema` ...
db: sys
exec_count: 2
total_latency: 16.75 s
memory_tmp_tables: 378
disk_tmp_tables: 66
avg_tmp_tables_per_query: 189
tmp_tables_to_disk_pct: 17
first_seen: 2014-03-07 13:13:41
last_seen: 2014-03-07 13:13:48
digest: 54f9bd520f0bbf15db0c2ed93386bec9
```
#### user_summary / x$user_summary
##### Description
Summarizes statement activity, file IO and connections by user.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures (5.7)
```SQL
mysql> desc user_summary;
+------------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| statements | decimal(64,0) | YES | | NULL | |
| statement_latency | text | YES | | NULL | |
| statement_avg_latency | text | YES | | NULL | |
| table_scans | decimal(65,0) | YES | | NULL | |
| file_ios | decimal(64,0) | YES | | NULL | |
| file_io_latency | text | YES | | NULL | |
| current_connections | decimal(41,0) | YES | | NULL | |
| total_connections | decimal(41,0) | YES | | NULL | |
| unique_hosts | bigint(21) | NO | | 0 | |
| current_memory | text | YES | | NULL | |
| total_memory_allocated | text | YES | | NULL | |
+------------------------+---------------+------+-----+---------+-------+
12 rows in set (0.00 sec)
mysql> desc x$user_summary;
+------------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| statements | decimal(64,0) | YES | | NULL | |
| statement_latency | decimal(64,0) | YES | | NULL | |
| statement_avg_latency | decimal(65,4) | NO | | 0.0000 | |
| table_scans | decimal(65,0) | YES | | NULL | |
| file_ios | decimal(64,0) | YES | | NULL | |
| file_io_latency | decimal(64,0) | YES | | NULL | |
| current_connections | decimal(41,0) | YES | | NULL | |
| total_connections | decimal(41,0) | YES | | NULL | |
| unique_hosts | bigint(21) | NO | | 0 | |
| current_memory | decimal(63,0) | YES | | NULL | |
| total_memory_allocated | decimal(64,0) | YES | | NULL | |
+------------------------+---------------+------+-----+---------+-------+
12 rows in set (0.01 sec)
```
##### Example
```SQL
mysql> select * from user_summary\G
*************************** 1. row ***************************
user: root
statements: 4981
statement_latency: 26.54 s
statement_avg_latency: 5.33 ms
table_scans: 74
file_ios: 7792
file_io_latency: 40.08 s
current_connections: 1
total_connections: 2
unique_hosts: 1
current_memory: 3.57 MiB
total_memory_allocated: 83.37 MiB
*************************** 2. row ***************************
user: background
statements: 0
statement_latency: 0 ps
statement_avg_latency: 0 ps
table_scans: 0
file_ios: 1618
file_io_latency: 4.78 s
current_connections: 21
total_connections: 23
unique_hosts: 0
current_memory: 165.94 MiB
total_memory_allocated: 197.29 MiB
```
#### user_summary_by_file_io / x$user_summary_by_file_io
##### Description
Summarizes file IO totals per user.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc user_summary_by_file_io;
+------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| ios | decimal(42,0) | YES | | NULL | |
| io_latency | text | YES | | NULL | |
+------------+---------------+------+-----+---------+-------+
3 rows in set (0.20 sec)
mysql> desc x$user_summary_by_file_io;
+------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| ios | decimal(42,0) | YES | | NULL | |
| io_latency | decimal(42,0) | YES | | NULL | |
+------------+---------------+------+-----+---------+-------+
3 rows in set (0.02 sec)
```
##### Example
```SQL
mysql> select * from user_summary_by_file_io;
+------------+-------+------------+
| user | ios | io_latency |
+------------+-------+------------+
| root | 26457 | 21.58 s |
| background | 1189 | 394.21 ms |
+------------+-------+------------+
```
#### user_summary_by_file_io_type / x$user_summary_by_file_io_type
##### Description
Summarizes file IO by event type per user.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc user_summary_by_file_io_type;
+-------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+-------------+---------------------+------+-----+---------+-------+
5 rows in set (0.02 sec)
mysql> desc x$user_summary_by_file_io_type;
+-------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
+-------------+---------------------+------+-----+---------+-------+
5 rows in set (0.00 sec)
```
##### Example
```SQL
mysql> select * from user_summary_by_file_io_type;
+------------+--------------------------------------+-------+-----------+-------------+
| user | event_name | total | latency | max_latency |
+------------+--------------------------------------+-------+-----------+-------------+
| background | wait/io/file/innodb/innodb_data_file | 1434 | 3.29 s | 147.56 ms |
| background | wait/io/file/sql/FRM | 910 | 286.61 ms | 32.92 ms |
| background | wait/io/file/sql/relaylog | 9 | 252.28 ms | 144.17 ms |
| background | wait/io/file/sql/binlog | 56 | 193.73 ms | 153.72 ms |
| background | wait/io/file/sql/binlog_index | 22 | 183.02 ms | 81.83 ms |
| background | wait/io/file/innodb/innodb_log_file | 20 | 117.17 ms | 36.53 ms |
| background | wait/io/file/sql/relaylog_index | 9 | 50.15 ms | 48.04 ms |
| background | wait/io/file/sql/ERRMSG | 5 | 35.41 ms | 31.78 ms |
| background | wait/io/file/myisam/kfile | 67 | 18.14 ms | 9.00 ms |
| background | wait/io/file/mysys/charset | 3 | 7.46 ms | 4.13 ms |
| background | wait/io/file/sql/casetest | 5 | 6.01 ms | 5.86 ms |
| background | wait/io/file/sql/pid | 3 | 5.96 ms | 3.06 ms |
| background | wait/io/file/myisam/dfile | 43 | 980.38 us | 152.46 us |
| background | wait/io/file/mysys/cnf | 5 | 154.97 us | 58.87 us |
| background | wait/io/file/sql/global_ddl_log | 2 | 18.64 us | 16.40 us |
| root | wait/io/file/sql/file_parser | 11048 | 48.79 s | 201.11 ms |
| root | wait/io/file/innodb/innodb_data_file | 4699 | 3.02 s | 46.93 ms |
| root | wait/io/file/sql/FRM | 10403 | 2.38 s | 61.72 ms |
| root | wait/io/file/myisam/dfile | 22143 | 726.77 ms | 308.79 ms |
| root | wait/io/file/myisam/kfile | 6213 | 435.35 ms | 88.76 ms |
| root | wait/io/file/sql/dbopt | 159 | 130.86 ms | 15.46 ms |
| root | wait/io/file/csv/metadata | 8 | 86.60 ms | 50.32 ms |
| root | wait/io/file/sql/binlog | 15 | 38.79 ms | 9.40 ms |
| root | wait/io/file/sql/misc | 21 | 22.33 ms | 15.30 ms |
| root | wait/io/file/csv/data | 4 | 297.46 us | 111.93 us |
| root | wait/io/file/archive/data | 3 | 54.10 us | 40.74 us |
+------------+--------------------------------------+-------+-----------+-------------+
```
#### user_summary_by_stages / x$user_summary_by_stages
##### Description
Summarizes stages by user, ordered by user and total latency per stage.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc user_summary_by_stages;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.01 sec)
mysql> desc x$user_summary_by_stages;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| user | varchar(16) | YES | | NULL | |
| event_name | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.05 sec)
```
##### Example
```SQL
mysql> select * from user_summary_by_stages;
+------+--------------------------------+-------+---------------+-------------+
| user | event_name | total | total_latency | avg_latency |
+------+--------------------------------+-------+---------------+-------------+
| root | stage/sql/Opening tables | 889 | 1.97 ms | 2.22 us |
| root | stage/sql/Creating sort index | 4 | 1.79 ms | 446.30 us |
| root | stage/sql/init | 10 | 312.27 us | 31.23 us |
| root | stage/sql/checking permissions | 10 | 300.62 us | 30.06 us |
| root | stage/sql/freeing items | 5 | 85.89 us | 17.18 us |
| root | stage/sql/statistics | 5 | 79.15 us | 15.83 us |
| root | stage/sql/preparing | 5 | 69.12 us | 13.82 us |
| root | stage/sql/optimizing | 5 | 53.11 us | 10.62 us |
| root | stage/sql/Sending data | 5 | 44.66 us | 8.93 us |
| root | stage/sql/closing tables | 5 | 37.54 us | 7.51 us |
| root | stage/sql/System lock | 5 | 34.28 us | 6.86 us |
| root | stage/sql/query end | 5 | 24.37 us | 4.87 us |
| root | stage/sql/end | 5 | 8.60 us | 1.72 us |
| root | stage/sql/Sorting result | 5 | 8.33 us | 1.67 us |
| root | stage/sql/executing | 5 | 5.37 us | 1.07 us |
| root | stage/sql/cleaning up | 5 | 4.60 us | 919.00 ns |
+------+--------------------------------+-------+---------------+-------------+
```
#### user_summary_by_statement_latency / x$user_summary_by_statement_latency
##### Description
Summarizes overall statement statistics by user.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc user_summary_by_statement_latency;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_sent | decimal(42,0) | YES | | NULL | |
| rows_examined | decimal(42,0) | YES | | NULL | |
| rows_affected | decimal(42,0) | YES | | NULL | |
| full_scans | decimal(43,0) | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
9 rows in set (0.00 sec)
mysql> desc x$user_summary_by_statement_latency;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | decimal(42,0) | YES | | NULL | |
| max_latency | decimal(42,0) | YES | | NULL | |
| lock_latency | decimal(42,0) | YES | | NULL | |
| rows_sent | decimal(42,0) | YES | | NULL | |
| rows_examined | decimal(42,0) | YES | | NULL | |
| rows_affected | decimal(42,0) | YES | | NULL | |
| full_scans | decimal(43,0) | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
9 rows in set (0.28 sec)
```
##### Example
```SQL
mysql> select * from user_summary_by_statement_latency;
+------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| user | total | total_latency | max_latency | lock_latency | rows_sent | rows_examined | rows_affected | full_scans |
+------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| root | 3381 | 00:02:09.13 | 1.48 s | 1.07 s | 1151 | 93947 | 150 | 91 |
+------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
```
#### user_summary_by_statement_type / x$user_summary_by_statement_type
##### Description
Summarizes the types of statements executed by each user.
When the user found is NULL, it is assumed to be a "background" thread.
##### Structures
```SQL
mysql> desc user_summary_by_statement_type;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| statement | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
| lock_latency | text | YES | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_affected | bigint(20) unsigned | NO | | NULL | |
| full_scans | bigint(21) unsigned | NO | | 0 | |
+---------------+---------------------+------+-----+---------+-------+
10 rows in set (0.21 sec)
mysql> desc x$user_summary_by_statement_type;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| statement | varchar(128) | YES | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
| lock_latency | bigint(20) unsigned | NO | | NULL | |
| rows_sent | bigint(20) unsigned | NO | | NULL | |
| rows_examined | bigint(20) unsigned | NO | | NULL | |
| rows_affected | bigint(20) unsigned | NO | | NULL | |
| full_scans | bigint(21) unsigned | NO | | 0 | |
+---------------+---------------------+------+-----+---------+-------+
10 rows in set (0.37 sec)
```
##### Example
```SQL
mysql> select * from user_summary_by_statement_type;
+------+------------------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| user | statement | total | total_latency | max_latency | lock_latency | rows_sent | rows_examined | rows_affected | full_scans |
+------+------------------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
| root | create_view | 1332 | 00:03:39.08 | 677.76 ms | 494.56 ms | 0 | 0 | 0 | 0 |
| root | select | 88 | 20.13 s | 16.57 s | 17.40 s | 1804 | 77285 | 0 | 48 |
| root | drop_db | 16 | 6.83 s | 1.14 s | 5.73 s | 0 | 0 | 953 | 0 |
| root | drop_view | 392 | 1.70 s | 739.49 ms | 0 ps | 0 | 0 | 0 | 0 |
| root | show_databases | 16 | 1.37 s | 587.44 ms | 1.31 ms | 400 | 400 | 0 | 16 |
| root | show_tables | 34 | 676.78 ms | 167.04 ms | 3.46 ms | 1087 | 1087 | 0 | 34 |
| root | create_db | 22 | 334.90 ms | 38.93 ms | 0 ps | 0 | 0 | 22 | 0 |
| root | create_procedure | 352 | 250.02 ms | 21.90 ms | 165.17 ms | 0 | 0 | 0 | 0 |
| root | drop_function | 176 | 122.44 ms | 69.18 ms | 87.24 ms | 0 | 0 | 0 | 0 |
| root | create_function | 176 | 76.12 ms | 1.36 ms | 49.50 ms | 0 | 0 | 0 | 0 |
| root | drop_procedure | 352 | 67.41 ms | 1.57 ms | 36.22 ms | 0 | 0 | 0 | 0 |
| root | update | 2 | 41.75 ms | 35.96 ms | 35.52 ms | 0 | 557 | 338 | 0 |
| root | error | 3 | 17.22 ms | 17.05 ms | 0 ps | 0 | 0 | 0 | 0 |
| root | set_option | 88 | 8.02 ms | 1.63 ms | 0 ps | 0 | 0 | 0 | 0 |
| root | call_procedure | 2 | 2.98 ms | 2.29 ms | 95.00 us | 0 | 0 | 0 | 0 |
| root | Init DB | 22 | 1.07 ms | 117.65 us | 0 ps | 0 | 0 | 0 | 0 |
| root | show_status | 1 | 408.69 us | 408.69 us | 102.00 us | 23 | 23 | 0 | 1 |
+------+------------------+-------+---------------+-------------+--------------+-----------+---------------+---------------+------------+
```
#### wait_classes_global_by_avg_latency / x$wait_classes_global_by_avg_latency
##### Description
Lists the top wait classes by average latency, ignoring idle (this may be very large).
##### Structures
```SQL
mysql> desc wait_classes_global_by_avg_latency;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| event_class | varchar(128) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | text | YES | | NULL | |
| min_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
6 rows in set (0.11 sec)
mysql> desc x$wait_classes_global_by_avg_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| event_class | varchar(128) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | decimal(42,0) | YES | | NULL | |
| min_latency | bigint(20) unsigned | YES | | NULL | |
| avg_latency | decimal(46,4) | NO | | 0.0000 | |
| max_latency | bigint(20) unsigned | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
6 rows in set (0.02 sec)
```
##### Example
```SQL
mysql> select * from wait_classes_global_by_avg_latency where event_class != 'idle';
+-------------------+--------+---------------+-------------+-------------+-------------+
| event_class | total | total_latency | min_latency | avg_latency | max_latency |
+-------------------+--------+---------------+-------------+-------------+-------------+
| wait/io/file | 543123 | 44.60 s | 19.44 ns | 82.11 us | 4.21 s |
| wait/io/table | 22002 | 766.60 ms | 148.72 ns | 34.84 us | 44.97 ms |
| wait/io/socket | 79613 | 967.17 ms | 0 ps | 12.15 us | 27.10 ms |
| wait/lock/table | 35409 | 18.68 ms | 65.45 ns | 527.51 ns | 969.88 us |
| wait/synch/rwlock | 37935 | 4.61 ms | 21.38 ns | 121.61 ns | 34.65 us |
| wait/synch/mutex | 390622 | 18.60 ms | 19.44 ns | 47.61 ns | 10.32 us |
+-------------------+--------+---------------+-------------+-------------+-------------+
```
#### wait_classes_global_by_latency / x$wait_classes_global_by_latency
##### Description
Lists the top wait classes by total latency, ignoring idle (this may be very large).
##### Structures
```SQL
mysql> desc wait_classes_global_by_latency;
+---------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------+------+-----+---------+-------+
| event_class | varchar(128) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | text | YES | | NULL | |
| min_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+---------------+---------------+------+-----+---------+-------+
6 rows in set (0.00 sec)
mysql> desc x$wait_classes_global_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| event_class | varchar(128) | YES | | NULL | |
| total | decimal(42,0) | YES | | NULL | |
| total_latency | decimal(42,0) | YES | | NULL | |
| min_latency | bigint(20) unsigned | YES | | NULL | |
| avg_latency | decimal(46,4) | NO | | 0.0000 | |
| max_latency | bigint(20) unsigned | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
6 rows in set (0.02 sec)
```
##### Example
```SQL
mysql> select * from wait_classes_global_by_latency;
+-------------------+--------+---------------+-------------+-------------+-------------+
| event_class | total | total_latency | min_latency | avg_latency | max_latency |
+-------------------+--------+---------------+-------------+-------------+-------------+
| wait/io/file | 550470 | 46.01 s | 19.44 ns | 83.58 us | 4.21 s |
| wait/io/socket | 228833 | 2.71 s | 0 ps | 11.86 us | 29.93 ms |
| wait/io/table | 64063 | 1.89 s | 99.79 ns | 29.43 us | 68.07 ms |
| wait/lock/table | 76029 | 47.19 ms | 65.45 ns | 620.74 ns | 969.88 us |
| wait/synch/mutex | 635925 | 34.93 ms | 19.44 ns | 54.93 ns | 107.70 us |
| wait/synch/rwlock | 61287 | 7.62 ms | 21.38 ns | 124.37 ns | 34.65 us |
+-------------------+--------+---------------+-------------+-------------+-------------+
```
#### waits_by_user_by_latency / x$waits_by_user_by_latency
##### Description
Lists the top wait events per user by their total latency, ignoring idle (this may be very large) per user.
##### Structures
```SQL
mysql> desc waits_by_user_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| event | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
6 rows in set (0.00 sec)
mysql> desc x$waits_by_user_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| user | varchar(32) | YES | | NULL | |
| event | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
6 rows in set (0.30 sec)
```
##### Example
```SQL
mysql> select * from waits_by_user_by_latency;
+------+-----------------------------------------------------+--------+---------------+-------------+-------------+
| user | event | total | total_latency | avg_latency | max_latency |
+------+-----------------------------------------------------+--------+---------------+-------------+-------------+
| root | wait/io/file/sql/file_parser | 13743 | 00:01:00.46 | 4.40 ms | 231.88 ms |
| root | wait/io/file/innodb/innodb_data_file | 4699 | 3.02 s | 643.38 us | 46.93 ms |
| root | wait/io/file/sql/FRM | 11462 | 2.60 s | 226.83 us | 61.72 ms |
| root | wait/io/file/myisam/dfile | 26776 | 746.70 ms | 27.89 us | 308.79 ms |
| root | wait/io/file/myisam/kfile | 7126 | 462.66 ms | 64.93 us | 88.76 ms |
| root | wait/io/file/sql/dbopt | 179 | 137.58 ms | 768.59 us | 15.46 ms |
| root | wait/io/file/csv/metadata | 8 | 86.60 ms | 10.82 ms | 50.32 ms |
| root | wait/synch/mutex/mysys/IO_CACHE::append_buffer_lock | 798080 | 66.46 ms | 82.94 ns | 161.03 us |
| root | wait/io/file/sql/binlog | 19 | 49.11 ms | 2.58 ms | 9.40 ms |
| root | wait/io/file/sql/misc | 26 | 22.38 ms | 860.80 us | 15.30 ms |
| root | wait/io/file/csv/data | 4 | 297.46 us | 74.37 us | 111.93 us |
| root | wait/synch/rwlock/sql/MDL_lock::rwlock | 944 | 287.86 us | 304.62 ns | 874.64 ns |
| root | wait/io/file/archive/data | 4 | 82.71 us | 20.68 us | 40.74 us |
| root | wait/synch/mutex/myisam/MYISAM_SHARE::intern_lock | 60 | 12.21 us | 203.20 ns | 512.72 ns |
| root | wait/synch/mutex/innodb/trx_mutex | 81 | 5.93 us | 73.14 ns | 252.59 ns |
+------+-----------------------------------------------------+--------+---------------+-------------+-------------+
```
#### waits_by_host_by_latency / x$waits_by_host_by_latency
##### Description
Lists the top wait events per host by their total latency, ignoring idle (this may be very large) per host.
##### Structures
```SQL
mysql> desc waits_by_host_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| event | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
6 rows in set (0.36 sec)
mysql> desc x$waits_by_host_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| host | varchar(60) | YES | | NULL | |
| event | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
6 rows in set (0.25 sec)
```
##### Example
```SQL
mysql> select * from waits_by_host_by_latency;
+------+-----------------------------------------------------+--------+---------------+-------------+-------------+
| host | event | total | total_latency | avg_latency | max_latency |
+------+-----------------------------------------------------+--------+---------------+-------------+-------------+
| hal1 | wait/io/file/sql/file_parser | 13743 | 00:01:00.46 | 4.40 ms | 231.88 ms |
| hal1 | wait/io/file/innodb/innodb_data_file | 4699 | 3.02 s | 643.38 us | 46.93 ms |
| hal1 | wait/io/file/sql/FRM | 11462 | 2.60 s | 226.83 us | 61.72 ms |
| hal1 | wait/io/file/myisam/dfile | 26776 | 746.70 ms | 27.89 us | 308.79 ms |
| hal1 | wait/io/file/myisam/kfile | 7126 | 462.66 ms | 64.93 us | 88.76 ms |
| hal1 | wait/io/file/sql/dbopt | 179 | 137.58 ms | 768.59 us | 15.46 ms |
| hal1 | wait/io/file/csv/metadata | 8 | 86.60 ms | 10.82 ms | 50.32 ms |
| hal1 | wait/synch/mutex/mysys/IO_CACHE::append_buffer_lock | 798080 | 66.46 ms | 82.94 ns | 161.03 us |
| hal1 | wait/io/file/sql/binlog | 19 | 49.11 ms | 2.58 ms | 9.40 ms |
| hal1 | wait/io/file/sql/misc | 26 | 22.38 ms | 860.80 us | 15.30 ms |
| hal1 | wait/io/file/csv/data | 4 | 297.46 us | 74.37 us | 111.93 us |
| hal1 | wait/synch/rwlock/sql/MDL_lock::rwlock | 944 | 287.86 us | 304.62 ns | 874.64 ns |
| hal1 | wait/io/file/archive/data | 4 | 82.71 us | 20.68 us | 40.74 us |
| hal1 | wait/synch/mutex/myisam/MYISAM_SHARE::intern_lock | 60 | 12.21 us | 203.20 ns | 512.72 ns |
| hal1 | wait/synch/mutex/innodb/trx_mutex | 81 | 5.93 us | 73.14 ns | 252.59 ns |
+------+-----------------------------------------------------+--------+---------------+-------------+-------------+
```
#### waits_global_by_latency / x$waits_global_by_latency
##### Description
Lists the top wait events by their total latency, ignoring idle (this may be very large).
##### Structures
```SQL
mysql> desc waits_global_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| events | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | text | YES | | NULL | |
| avg_latency | text | YES | | NULL | |
| max_latency | text | YES | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.01 sec)
mysql> desc x$waits_global_by_latency;
+---------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+---------------------+------+-----+---------+-------+
| events | varchar(128) | NO | | NULL | |
| total | bigint(20) unsigned | NO | | NULL | |
| total_latency | bigint(20) unsigned | NO | | NULL | |
| avg_latency | bigint(20) unsigned | NO | | NULL | |
| max_latency | bigint(20) unsigned | NO | | NULL | |
+---------------+---------------------+------+-----+---------+-------+
5 rows in set (0.03 sec)
```
##### Example
```SQL
mysql> select * from waits_global_by_latency;
+-----------------------------------------------------+---------+---------------+-------------+-------------+
| events | total | total_latency | avg_latency | max_latency |
+-----------------------------------------------------+---------+---------------+-------------+-------------+
| wait/io/file/sql/file_parser | 14936 | 00:01:06.64 | 4.46 ms | 231.88 ms |
| wait/io/file/innodb/innodb_data_file | 6133 | 6.31 s | 1.03 ms | 147.56 ms |
| wait/io/file/sql/FRM | 12677 | 2.83 s | 223.37 us | 40.86 ms |
| wait/io/file/myisam/dfile | 28446 | 754.40 ms | 26.52 us | 308.79 ms |
| wait/io/file/myisam/kfile | 7572 | 491.17 ms | 64.87 us | 88.76 ms |
| wait/io/file/sql/relaylog | 9 | 252.28 ms | 28.03 ms | 144.17 ms |
| wait/io/file/sql/binlog | 76 | 242.87 ms | 3.20 ms | 153.72 ms |
| wait/io/file/sql/binlog_index | 21 | 173.07 ms | 8.24 ms | 81.83 ms |
| wait/io/file/sql/dbopt | 184 | 149.52 ms | 812.62 us | 15.46 ms |
| wait/io/file/innodb/innodb_log_file | 20 | 117.17 ms | 5.86 ms | 36.53 ms |
| wait/synch/mutex/mysys/IO_CACHE::append_buffer_lock | 1197128 | 99.27 ms | 82.56 ns | 161.03 us |
| wait/io/file/csv/metadata | 8 | 86.60 ms | 10.82 ms | 50.32 ms |
| wait/io/file/sql/relaylog_index | 10 | 60.10 ms | 6.01 ms | 48.04 ms |
| wait/io/file/sql/ERRMSG | 5 | 35.41 ms | 7.08 ms | 31.78 ms |
| wait/io/file/sql/misc | 28 | 22.40 ms | 800.06 us | 15.30 ms |
| wait/io/file/mysys/charset | 3 | 7.46 ms | 2.49 ms | 4.13 ms |
| wait/io/file/sql/casetest | 5 | 6.01 ms | 1.20 ms | 5.86 ms |
| wait/io/file/sql/pid | 3 | 5.96 ms | 1.99 ms | 3.06 ms |
| wait/synch/rwlock/sql/MDL_lock::rwlock | 1396 | 420.58 us | 301.22 ns | 874.64 ns |
| wait/io/file/csv/data | 4 | 297.46 us | 74.37 us | 111.93 us |
| wait/io/file/mysys/cnf | 5 | 154.97 us | 30.99 us | 58.87 us |
| wait/io/file/archive/data | 4 | 82.71 us | 20.68 us | 40.74 us |
| wait/synch/mutex/myisam/MYISAM_SHARE::intern_lock | 90 | 19.23 us | 213.38 ns | 576.81 ns |
| wait/io/file/sql/global_ddl_log | 2 | 18.64 us | 9.32 us | 16.40 us |
| wait/synch/mutex/innodb/trx_mutex | 108 | 8.23 us | 76.15 ns | 365.69 ns |
+-----------------------------------------------------+---------+---------------+-------------+-------------+
```
### Functions
#### extract_schema_from_file_name
##### Description
Takes a raw file path, and attempts to extract the schema name from it.
Useful for when interacting with Performance Schema data concerning IO statistics, for example.
Currently relies on the fact that a table data file will be within a specified database directory (will not work with partitions or tables that specify an individual DATA_DIRECTORY).
##### Parameters
* path (VARCHAR(512)): The full file path to a data file to extract the schema name from.
##### Returns
VARCHAR(64)
##### Example
```SQL
mysql> SELECT sys.extract_schema_from_file_name('/var/lib/mysql/employees/employee.ibd');
+----------------------------------------------------------------------------+
| sys.extract_schema_from_file_name('/var/lib/mysql/employees/employee.ibd') |
+----------------------------------------------------------------------------+
| employees |
+----------------------------------------------------------------------------+
1 row in set (0.00 sec)
```
#### extract_table_from_file_name
##### Description
Takes a raw file path, and extracts the table name from it.
Useful for when interacting with Performance Schema data concerning IO statistics, for example.
##### Parameters
* path (VARCHAR(512)): The full file path to a data file to extract the table name from.
##### Returns
VARCHAR(64)
##### Example
```SQL
mysql> SELECT sys.extract_table_from_file_name('/var/lib/mysql/employees/employee.ibd');
+---------------------------------------------------------------------------+
| sys.extract_table_from_file_name('/var/lib/mysql/employees/employee.ibd') |
+---------------------------------------------------------------------------+
| employee |
+---------------------------------------------------------------------------+
1 row in set (0.02 sec)
```
#### format_bytes
##### Description
Takes a raw bytes value, and converts it to a human readable format.
##### Parameters
* bytes (TEXT): A raw bytes value.
##### Returns
TEXT
##### Example
```SQL
mysql> SELECT sys.format_bytes(2348723492723746) AS size;
+----------+
| size |
+----------+
| 2.09 PiB |
+----------+
1 row in set (0.00 sec)
mysql> SELECT sys.format_bytes(2348723492723) AS size;
+----------+
| size |
+----------+
| 2.14 TiB |
+----------+
1 row in set (0.00 sec)
mysql> SELECT sys.format_bytes(23487234) AS size;
+-----------+
| size |
+-----------+
| 22.40 MiB |
+-----------+
1 row in set (0.00 sec)
```
#### format_path
##### Description
Takes a raw path value, and strips out the datadir or tmpdir replacing with @@datadir and @@tmpdir respectively.
Also normalizes the paths across operating systems, so backslashes on Windows are converted to forward slashes.
##### Parameters
* path (VARCHAR(512)): The raw file path value to format.
##### Returns
VARCHAR(512) CHARSET UTF8
##### Example
```SQL
mysql> select @@datadir;
+-----------------------------------------------+
| @@datadir |
+-----------------------------------------------+
| /Users/mark/sandboxes/SmallTree/AMaster/data/ |
+-----------------------------------------------+
1 row in set (0.06 sec)
mysql> select format_path('/Users/mark/sandboxes/SmallTree/AMaster/data/mysql/proc.MYD') AS path;
+--------------------------+
| path |
+--------------------------+
| @@datadir/mysql/proc.MYD |
+--------------------------+
1 row in set (0.03 sec)
```
#### format_statement
##### Description
Formats a normalized statement, truncating it if it is > 64 characters long by default.
To configure the length to truncate the statement to by default, update the `statement_truncate_len` variable with `sys_config` table to a different value. Alternatively, to change it just for just your particular session, use `SET @sys.statement_truncate_len := <some new value>`.
Useful for printing statement related data from Performance Schema from the command line.
##### Parameters
* statement (LONGTEXT): The statement to format.
##### Returns
VARCHAR(65)
##### Example
```SQL
mysql> SELECT sys.format_statement(digest_text)
-> FROM performance_schema.events_statements_summary_by_digest
-> ORDER by sum_timer_wait DESC limit 5;
+-------------------------------------------------------------------+
| sys.format_statement(digest_text) |
+-------------------------------------------------------------------+
| CREATE SQL SECURITY INVOKER VI ... KE ? AND `variable_value` > ? |
| CREATE SQL SECURITY INVOKER VI ... ait` IS NOT NULL , `esc` . ... |
| CREATE SQL SECURITY INVOKER VI ... ait` IS NOT NULL , `sys` . ... |
| CREATE SQL SECURITY INVOKER VI ... , `compressed_size` ) ) DESC |
| CREATE SQL SECURITY INVOKER VI ... LIKE ? ORDER BY `timer_start` |
+-------------------------------------------------------------------+
5 rows in set (0.00 sec)
```
#### format_time
##### Description
Takes a raw picoseconds value, and converts it to a human readable form.
Picoseconds are the precision that all latency values are printed in within Performance Schema, however are not user friendly when wanting to scan output from the command line.
##### Parameters
* picoseconds (TEXT): The raw picoseconds value to convert.
##### Returns
TEXT
##### Example
```SQL
mysql> select format_time(342342342342345);
+------------------------------+
| format_time(342342342342345) |
+------------------------------+
| 00:05:42 |
+------------------------------+
1 row in set (0.00 sec)
mysql> select format_time(342342342);
+------------------------+
| format_time(342342342) |
+------------------------+
| 342.34 us |
+------------------------+
1 row in set (0.00 sec)
mysql> select format_time(34234);
+--------------------+
| format_time(34234) |
+--------------------+
| 34.23 ns |
+--------------------+
1 row in set (0.00 sec)
```
#### list_add
##### Description
Takes a list, and a value to add to the list, and returns the resulting list.
Useful for altering certain session variables, like sql_mode or optimizer_switch for instance.
##### Parameters
in_list (TEXT): The comma separated list to add a value to
in_add_value (TEXT): The value to add to the input list
##### Returns
TEXT
##### Example
```SQL
mysql> select @@sql_mode;
+-----------------------------------------------------------------------------------+
| @@sql_mode |
+-----------------------------------------------------------------------------------+
| ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+-----------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> set sql_mode = sys.list_add(@@sql_mode, 'ANSI_QUOTES');
Query OK, 0 rows affected (0.06 sec)
mysql> select @@sql_mode;
+-----------------------------------------------------------------------------------------------+
| @@sql_mode |
+-----------------------------------------------------------------------------------------------+
| ANSI_QUOTES,ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+-----------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
```
#### list_drop
##### Description
Takes a list, and a value to attempt to remove from the list, and returns the resulting list.
Useful for altering certain session variables, like sql_mode or optimizer_switch for instance.
##### Parameters
in_list (TEXT): The comma separated list to drop a value from
in_drop_value (TEXT): The value to drop from the input list
##### Returns
TEXT
##### Example
```SQL
mysql> select @@sql_mode;
+-----------------------------------------------------------------------------------------------+
| @@sql_mode |
+-----------------------------------------------------------------------------------------------+
| ANSI_QUOTES,ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+-----------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> set sql_mode = sys.list_drop(@@sql_mode, 'ONLY_FULL_GROUP_BY');
Query OK, 0 rows affected (0.03 sec)
mysql> select @@sql_mode;
+----------------------------------------------------------------------------+
| @@sql_mode |
+----------------------------------------------------------------------------+
| ANSI_QUOTES,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+----------------------------------------------------------------------------+
1 row in set (0.00 sec)
```
#### ps_is_account_enabled
##### Description
Determines whether instrumentation of an account is enabled within Performance Schema.
##### Parameters
* in_host VARCHAR(60): The hostname of the account to check.
* in_user VARCHAR(32): The username of the account to check.
##### Returns
ENUM('YES', 'NO')
##### Example
```SQL
mysql> SELECT sys.ps_is_account_enabled('localhost', 'root');
+------------------------------------------------+
| sys.ps_is_account_enabled('localhost', 'root') |
+------------------------------------------------+
| YES |
+------------------------------------------------+
1 row in set (0.01 sec)
```
#### ps_is_consumer_enabled
##### Description
Determines whether a consumer is enabled (taking the consumer hierarchy into consideration) within the Performance Schema.
##### Parameters
* in_consumer VARCHAR(64): The name of the consumer to check.
##### Returns
ENUM('YES', 'NO')
##### Example
```SQL
mysql> SELECT sys.ps_is_consumer_enabled('events_stages_history');
+-----------------------------------------------------+
| sys.ps_is_consumer_enabled('events_stages_history') |
+-----------------------------------------------------+
| NO |
+-----------------------------------------------------+
1 row in set (0.00 sec)
```
#### ps_is_instrument_default_enabled
##### Description
Returns whether an instrument is enabled by default in this version of MySQL.
##### Parameters
* in_instrument VARCHAR(128): The instrument to check.
##### Returns
ENUM('YES', 'NO')
##### Example
```SQL
mysql> SELECT sys.ps_is_instrument_default_enabled('statement/sql/select');
+--------------------------------------------------------------+
| sys.ps_is_instrument_default_enabled('statement/sql/select') |
+--------------------------------------------------------------+
| YES |
+--------------------------------------------------------------+
1 row in set (0.00 sec)
```
#### ps_is_instrument_default_timed
##### Description
Returns whether an instrument is timed by default in this version of MySQL.
##### Parameters
* in_instrument VARCHAR(128): The instrument to check.
##### Returns
ENUM('YES', 'NO')
##### Example
```SQL
mysql> SELECT sys.ps_is_instrument_default_timed('statement/sql/select');
+------------------------------------------------------------+
| sys.ps_is_instrument_default_timed('statement/sql/select') |
+------------------------------------------------------------+
| YES |
+------------------------------------------------------------+
1 row in set (0.00 sec)
```
#### ps_is_thread_instrumented
##### Description
Checks whether the provided connection id is instrumented within Performance Schema.
##### Parameters
* in_connection_id (BIGINT UNSIGNED): the id of the connection to check.
##### Returns
ENUM('YES', 'NO', 'UNKNOWN')
##### Example
```SQL
mysql> SELECT sys.ps_is_thread_instrumented(CONNECTION_ID());
+------------------------------------------------+
| sys.ps_is_thread_instrumented(CONNECTION_ID()) |
+------------------------------------------------+
| YES |
+------------------------------------------------+
1 row in set (0.10 sec)
```
#### ps_thread_id
##### Description
Return the Performance Schema THREAD_ID for the specified connection ID.
##### Parameters
* in_connection_id (BIGINT UNSIGNED): The id of the connection to return the thread id for. If NULL, the current connection thread id is returned.
##### Returns
BIGINT UNSIGNED
##### Example
```SQL
mysql> SELECT sys.ps_thread_id(79);
+----------------------+
| sys.ps_thread_id(79) |
+----------------------+
| 98 |
+----------------------+
1 row in set (0.00 sec)
mysql> SELECT sys.ps_thread_id(CONNECTION_ID());
+-----------------------------------+
| sys.ps_thread_id(CONNECTION_ID()) |
+-----------------------------------+
| 98 |
+-----------------------------------+
1 row in set (0.00 sec)
```
#### ps_thread_stack
##### Description
Outputs a JSON formatted stack of all statements, stages and events within Performance Schema for the specified thread.
##### Parameters
* thd_id (BIGINT): The id of the thread to trace. This should match the thread_id column from the performance_schema.threads table.
##### Example
(line separation added for output)
```SQL
mysql> SELECT sys.ps_thread_stack(37, FALSE) AS thread_stack\G
*************************** 1. row ***************************
thread_stack: {"rankdir": "LR","nodesep": "0.10","stack_created": "2014-02-19 13:39:03",
"mysql_version": "5.7.3-m13","mysql_user": "root@localhost","events":
[{"nesting_event_id": "0", "event_id": "10", "timer_wait": 256.35, "event_info":
"sql/select", "wait_info": "select @@version_comment limit 1\nerrors: 0\nwarnings: 0\nlock time:
...
```
#### ps_thread_trx_info
##### Description
Returns a JSON object with info on the given thread's current transaction, and the statements it has already executed, derived from the `performance_schema.events_transactions_current` and `performance_schema.events_statements_history` tables (so the consumers for these also have to be enabled within Performance Schema to get full data in the object).
When the output exceeds the default truncation length (65535), a JSON error object is returned, such as:
`{ "error": "Trx info truncated: Row 6 was cut by GROUP_CONCAT()" }`
Similar error objects are returned for other warnings/and exceptions raised when calling the function.
The max length of the output of this function can be controlled with the `ps_thread_trx_info.max_length` variable set via `sys_config`, or the `@sys.ps_thread_trx_info.max_length` user variable, as appropriate.
##### Parameters
* in_thread_id (BIGINT UNSIGNED): The id of the thread to return the transaction info for.
##### Example
```SQL
SELECT sys.ps_thread_trx_info(48)\G
*************************** 1. row ***************************
sys.ps_thread_trx_info(48): [
{
"time": "790.70 us",
"state": "COMMITTED",
"mode": "READ WRITE",
"autocommitted": "NO",
"gtid": "AUTOMATIC",
"isolation": "REPEATABLE READ",
"statements_executed": [
{
"sql_text": "INSERT INTO info VALUES (1, \'foo\')",
"time": "471.02 us",
"schema": "trx",
"rows_examined": 0,
"rows_affected": 1,
"rows_sent": 0,
"tmp_tables": 0,
"tmp_disk_tables": 0,
"sort_rows": 0,
"sort_merge_passes": 0
},
{
"sql_text": "COMMIT",
"time": "254.42 us",
"schema": "trx",
"rows_examined": 0,
"rows_affected": 0,
"rows_sent": 0,
"tmp_tables": 0,
"tmp_disk_tables": 0,
"sort_rows": 0,
"sort_merge_passes": 0
}
]
},
{
"time": "426.20 us",
"state": "COMMITTED",
"mode": "READ WRITE",
"autocommitted": "NO",
"gtid": "AUTOMATIC",
"isolation": "REPEATABLE READ",
"statements_executed": [
{
"sql_text": "INSERT INTO info VALUES (2, \'bar\')",
"time": "107.33 us",
"schema": "trx",
"rows_examined": 0,
"rows_affected": 1,
"rows_sent": 0,
"tmp_tables": 0,
"tmp_disk_tables": 0,
"sort_rows": 0,
"sort_merge_passes": 0
},
{
"sql_text": "COMMIT",
"time": "213.23 us",
"schema": "trx",
"rows_examined": 0,
"rows_affected": 0,
"rows_sent": 0,
"tmp_tables": 0,
"tmp_disk_tables": 0,
"sort_rows": 0,
"sort_merge_passes": 0
}
]
}
]
1 row in set (0.03 sec)
```
#### sys_get_config
##### Description
Returns the value for the requested variable using the following logic:
1. If the option exists in sys.sys_config return the value from there.
2. Else fall back on the provided default value.
Notes for using sys_get_config():
* If the default value argument to sys_get_config() is NULL and case 2. is reached, NULL is returned.
It is then expected that the caller is able to handle NULL for the given configuration option.
* The convention is to name the user variables @sys.<name of variable>. It is <name of variable> that
is stored in the sys_config table and is what is expected as the argument to sys_get_config().
* If you want to check whether the configuration option has already been set and if not assign with
the return value of sys_get_config() you can use IFNULL(...) (see example below). However this should
not be done inside a loop (e.g. for each row in a result set) as for repeated calls where assignment
is only needed in the first iteration using IFNULL(...) is expected to be significantly slower than
using an IF (...) THEN ... END IF; block (see example below).
##### Parameters
* in_variable_name (VARCHAR(128)): The name of the config option to return the value for.
* in_default_value (VARCHAR(128)): The default value to return if neither a use variable exists nor the variable exists in sys.sys_config.
##### Returns
VARCHAR(128)
##### Example
```SQL
-- Get the configuration value from sys.sys_config falling back on 128 if the option is not present in the table.
mysql> SELECT sys.sys_get_config('statement_truncate_len', 128) AS Value;
+-------+
| Value |
+-------+
| 64 |
+-------+
1 row in set (0.00 sec)
-- Check whether the option is already set, if not assign - IFNULL(...) one liner example.
mysql> SET @sys.statement_truncate_len = IFNULL(@sys.statement_truncate_len, sys.sys_get_config('statement_truncate_len', 64));
Query OK, 0 rows affected (0.00 sec)
-- Check whether the option is already set, if not assign - IF ... THEN ... END IF example.
IF (@sys.statement_truncate_len IS NULL) THEN
SET @sys.statement_truncate_len = sys.sys_get_config('statement_truncate_len', 64);
END IF;
```
#### version_major
##### Description
Returns the major version of MySQL Server.
##### Returns
TINYINT UNSIGNED
##### Example
```SQL
mysql> SELECT VERSION(), sys.version_major();
+--------------------------------------+---------------------+
| VERSION() | sys.version_major() |
+--------------------------------------+---------------------+
| 5.7.9-enterprise-commercial-advanced | 5 |
+--------------------------------------+---------------------+
1 row in set (0.00 sec)
```
#### version_minor
##### Description
Returns the minor (release series) version of MySQL Server.
##### Returns
TINYINT UNSIGNED
##### Example
```SQL
mysql> SELECT VERSION(), sys.server_minor();
+--------------------------------------+---------------------+
| VERSION() | sys.version_minor() |
+--------------------------------------+---------------------+
| 5.7.9-enterprise-commercial-advanced | 7 |
+--------------------------------------+---------------------+
1 row in set (0.00 sec)
```
#### version_patch
##### Description
Returns the patch release version of MySQL Server.
##### Returns
TINYINT UNSIGNED
##### Example
```SQL
mysql> SELECT VERSION(), sys.version_patch();
+--------------------------------------+---------------------+
| VERSION() | sys.version_patch() |
+--------------------------------------+---------------------+
| 5.7.9-enterprise-commercial-advanced | 9 |
+--------------------------------------+---------------------+
1 row in set (0.00 sec)
```
### Procedures
#### create_synonym_db
##### Description
Takes a source database name and synonym name, and then creates the synonym database with views that point to all of the tables within the source database.
Useful for creating a "ps" synonym for "performance_schema", or "is" instead of "information_schema", for example.
##### Parameters
* in_db_name (VARCHAR(64)):
** The database name that you would like to create a synonym for.
* in_synonym (VARCHAR(64)):
** The database synonym name.
##### Example
```SQL
mysql> SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
5 rows in set (0.00 sec)
mysql> CALL sys.create_synonym_db('performance_schema', 'ps');
+-------------------------------------+
| summary |
+-------------------------------------+
| Created 74 views in the ps database |
+-------------------------------------+
1 row in set (8.57 sec)
Query OK, 0 rows affected (8.57 sec)
mysql> SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| ps |
| sys |
| test |
+--------------------+
6 rows in set (0.00 sec)
mysql> SHOW FULL TABLES FROM ps;
+-----------------------------------------+------------+
| Tables_in_ps | Table_type |
+-----------------------------------------+------------+
| accounts | VIEW |
| cond_instances | VIEW |
| events_stages_current | VIEW |
| events_stages_history | VIEW |
...
```
#### execute_prepared_stmt
##### Description
Takes the query in the argument and executes it using a prepared statement. The prepared statement is deallocated,
so the procedure is mainly useful for executing one off dynamically created queries.
The sys_execute_prepared_stmt prepared statement name is used for the query and is required not to exist.
##### Parameters
* in_query (longtext CHARACTER SET UTF8):
** The query to execute.
The following configuration option is supported:
* sys.debug
Whether to provide debugging output.
Default is 'OFF'. Set to 'ON' to include.
##### Example
```SQL
mysql> CALL sys.execute_prepared_stmt(''SELECT * FROM sys.sys_config'');
+------------------------+-------+---------------------+--------+
| variable | value | set_time | set_by |
+------------------------+-------+---------------------+--------+
| statement_truncate_len | 64 | 2015-06-30 13:06:00 | NULL |
+------------------------+-------+---------------------+--------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
```
#### diagnostics
##### Description
Create a report of the current status of the server for diagnostics purposes. Data collected includes (some items depends on versions and settings):
* The GLOBAL VARIABLES
* Several sys schema views including metrics or equivalent (depending on version and settings)
* Queries in the 95th percentile
* Several ndbinfo views for MySQL Cluster
* Replication (both master and slave) information.
Some of the sys schema views are calculated as initial (optional), overall, delta:
* The initial view is the content of the view at the start of this procedure.
This output will be the same as the the start values used for the delta view.
The initial view is included if @sys.diagnostics.include_raw = 'ON'.
* The overall view is the content of the view at the end of this procedure.
This output is the same as the end values used for the delta view.
The overall view is always included.
* The delta view is the difference from the beginning to the end. Note that for min and max values
they are simply the min or max value from the end view respectively, so does not necessarily reflect
the minimum/maximum value in the monitored period.
Note: except for the metrics view the delta is only calculation between the first and last outputs.
Requires the SUPER privilege for "SET sql_log_bin = 0;".
Versions supported:
* MySQL 5.6: 5.6.10 and later
* MySQL 5.7: 5.7.9 and later
Some configuration options are supported:
* sys.diagnostics.allow_i_s_tables
Specifies whether it is allowed to do table scan queries on information_schema.TABLES. This can be expensive if there
are many tables. Set to 'ON' to allow, 'OFF' to not allow.
Default is 'OFF'.
* sys.diagnostics.include_raw
Set to 'ON' to include the raw data (e.g. the original output of "SELECT * FROM sys.metrics").
Use this to get the initial values of the various views.
Default is 'OFF'.
* sys.statement_truncate_len
How much of queries in the process list output to include.
Default is 64.
* sys.debug
Whether to provide debugging output.
Default is 'OFF'. Set to 'ON' to include.
##### Parameters
* in_max_runtime (INT UNSIGNED):
The maximum time to keep collecting data.
Use NULL to get the default which is 60 seconds, otherwise enter a value greater than 0.
* in_interval (INT UNSIGNED):
How long to sleep between data collections.
Use NULL to get the default which is 30 seconds, otherwise enter a value greater than 0.
* in_auto_config (ENUM('current', 'medium', 'full'))
Automatically enable Performance Schema instruments and consumers.
NOTE: The more that are enabled, the more impact on the performance.
If another setting the 'current' is chosen, the current settings
are restored at the end of the procedure.
Supported values are:
** current - use the current settings.
** medium - enable some settings. This requires the SUPER privilege.
** full - enables all settings. This will have a big impact on the
performance - be careful using this option. This requires the SUPER privilege.
##### Example
```SQL
mysql> TEE diag.out;
mysql> CALL sys.diagnostics(120, 30, 'current');
...
mysql> NOTEE;
```
#### ps_setup_disable_background_threads
##### Description
Disable all background thread instrumentation within Performance Schema.
##### Parameters
None.
##### Example
```SQL
mysql> CALL sys.ps_setup_disable_background_threads();
+--------------------------------+
| summary |
+--------------------------------+
| Disabled 18 background threads |
+--------------------------------+
1 row in set (0.00 sec)
```
#### ps_setup_disable_instrument
##### Description
Disables instruments within Performance Schema matching the input pattern.
##### Parameters
* in_pattern (VARCHAR(128)): A LIKE pattern match (using "%in_pattern%") of events to disable
##### Example
To disable all mutex instruments:
```SQL
mysql> CALL sys.ps_setup_disable_instrument('wait/synch/mutex');
+--------------------------+
| summary |
+--------------------------+
| Disabled 155 instruments |
+--------------------------+
1 row in set (0.02 sec)
```
To disable just a the scpecific TCP/IP based network IO instrument:
```SQL
mysql> CALL sys.ps_setup_disable_instrument('wait/io/socket/sql/server_tcpip_socket');
+------------------------+
| summary |
+------------------------+
| Disabled 1 instruments |
+------------------------+
1 row in set (0.00 sec)
```
To enable all instruments:
```SQL
mysql> CALL sys.ps_setup_disable_instrument('');
+--------------------------+
| summary |
+--------------------------+
| Disabled 547 instruments |
+--------------------------+
1 row in set (0.01 sec)
```
#### ps_setup_disable_consumer
##### Description
Disables consumers within Performance Schema matching the input pattern.
##### Parameters
* consumer (VARCHAR(128)): A LIKE pattern match (using "%consumer%") of consumers to disable
##### Example
To disable all consumers:
```SQL
mysql> CALL sys.ps_setup_disable_consumer('');
+--------------------------+
| summary |
+--------------------------+
| Disabled 15 consumers |
+--------------------------+
1 row in set (0.02 sec)
```
To disable just the event_stage consumers:
```SQL
mysql> CALL sys.ps_setup_disable_consumer('stage');
+------------------------+
| summary |
+------------------------+
| Disabled 3 consumers |
+------------------------+
1 row in set (0.00 sec)
```
#### ps_setup_disable_thread
##### Description
Disable the given connection/thread in Performance Schema.
##### Parameters
* in_connection_id (BIGINT): The connection ID (PROCESSLIST_ID from performance_schema.threads or the ID shown within SHOW PROCESSLIST)
##### Example
```SQL
mysql> CALL sys.ps_setup_disable_thread(3);
+-------------------+
| summary |
+-------------------+
| Disabled 1 thread |
+-------------------+
1 row in set (0.01 sec)
```
To disable the current connection:
```SQL
mysql> CALL sys.ps_setup_disable_thread(CONNECTION_ID());
+-------------------+
| summary |
+-------------------+
| Disabled 1 thread |
+-------------------+
1 row in set (0.00 sec)
```
#### ps_setup_enable_background_threads
##### Description
Enable all background thread instrumentation within Performance Schema.
##### Parameters
None.
##### Example
```SQL
mysql> CALL sys.ps_setup_enable_background_threads();
+-------------------------------+
| summary |
+-------------------------------+
| Enabled 18 background threads |
+-------------------------------+
1 row in set (0.00 sec)
```
#### ps_setup_enable_consumer
##### Description
Enables consumers within Performance Schema matching the input pattern.
##### Parameters
* consumer (VARCHAR(128)): A LIKE pattern match (using "%consumer%") of consumers to enable
##### Example
To enable all consumers:
```SQL
mysql> CALL sys.ps_setup_enable_consumer('');
+-------------------------+
| summary |
+-------------------------+
| Enabled 10 consumers |
+-------------------------+
1 row in set (0.02 sec)
```
To enable just "waits" consumers:
```SQL
mysql> CALL sys.ps_setup_enable_consumer('waits');
+-----------------------+
| summary |
+-----------------------+
| Enabled 3 consumers |
+-----------------------+
1 row in set (0.00 sec)
```
#### ps_setup_enable_instrument
##### Description
Enables instruments within Performance Schema matching the input pattern.
##### Parameters
* in_pattern (VARCHAR(128)): A LIKE pattern match (using "%in_pattern%") of events to enable
##### Example
To enable all mutex instruments:
```SQL
mysql> CALL sys.ps_setup_enable_instrument('wait/synch/mutex');
+-------------------------+
| summary |
+-------------------------+
| Enabled 155 instruments |
+-------------------------+
1 row in set (0.02 sec)
```
To enable just a the scpecific TCP/IP based network IO instrument:
```SQL
mysql> CALL sys.ps_setup_enable_instrument('wait/io/socket/sql/server_tcpip_socket');
+-----------------------+
| summary |
+-----------------------+
| Enabled 1 instruments |
+-----------------------+
1 row in set (0.00 sec)
```
To enable all instruments:
```SQL
mysql> CALL sys.ps_setup_enable_instrument('');
+-------------------------+
| summary |
+-------------------------+
| Enabled 547 instruments |
+-------------------------+
1 row in set (0.01 sec)
```
#### ps_setup_enable_thread
##### Description
Enable the given connection/thread in Performance Schema.
##### Parameters
* in_connection_id (BIGINT): The connection ID (PROCESSLIST_ID from performance_schema.threads or the ID shown within SHOW PROCESSLIST)
##### Example
```SQL
mysql> CALL sys.ps_setup_enable_thread(3);
+------------------+
| summary |
+------------------+
| Enabled 1 thread |
+------------------+
1 row in set (0.01 sec)
```
To enable the current connection:
```SQL
mysql> CALL sys.ps_setup_enable_thread(CONNECTION_ID());
+------------------+
| summary |
+------------------+
| Enabled 1 thread |
+------------------+
1 row in set (0.00 sec)
```
#### ps_setup_reload_saved
##### Description
Reloads a saved Performance Schema configuration, so that you can alter the setup for debugging purposes, but restore it to a previous state.
Use the companion procedure - ps_setup_save(), to save a configuration.
Requires the SUPER privilege for "SET sql_log_bin = 0;".
##### Parameters
None.
##### Example
```SQL
mysql> CALL sys.ps_setup_save();
Query OK, 0 rows affected (0.08 sec)
mysql> UPDATE performance_schema.setup_instruments SET enabled = 'YES', timed = 'YES';
Query OK, 547 rows affected (0.40 sec)
Rows matched: 784 Changed: 547 Warnings: 0
/* Run some tests that need more detailed instrumentation here */
mysql> CALL sys.ps_setup_reload_saved();
Query OK, 0 rows affected (0.32 sec)
```
#### ps_setup_reset_to_default
##### Description
Resets the Performance Schema setup to the default settings.
##### Parameters
* in_verbose (BOOLEAN): Whether to print each setup stage (including the SQL) whilst running.
##### Example
```SQL
mysql> CALL sys.ps_setup_reset_to_default(true)\G
*************************** 1. row ***************************
status: Resetting: setup_actors
DELETE
FROM performance_schema.setup_actors
WHERE NOT (HOST = '%' AND USER = '%' AND ROLE = '%')
1 row in set (0.00 sec)
*************************** 1. row ***************************
status: Resetting: setup_actors
INSERT IGNORE INTO performance_schema.setup_actors
VALUES ('%', '%', '%')
1 row in set (0.00 sec)
...
mysql> CALL sys.ps_setup_reset_to_default(false)G
Query OK, 0 rows affected (0.00 sec)
```
#### ps_setup_save
##### Description
Saves the current configuration of Performance Schema, so that you can alter the setup for debugging purposes, but restore it to a previous state.
Use the companion procedure - ps_setup_reload_saved(), to restore the saved config.
Requires the SUPER privilege for "SET sql_log_bin = 0;".
##### Parameters
None.
##### Example
```SQL
mysql> CALL sys.ps_setup_save();
Query OK, 0 rows affected (0.08 sec)
mysql> UPDATE performance_schema.setup_instruments
-> SET enabled = 'YES', timed = 'YES';
Query OK, 547 rows affected (0.40 sec)
Rows matched: 784 Changed: 547 Warnings: 0
/* Run some tests that need more detailed instrumentation here */
mysql> CALL sys.ps_setup_reload_saved();
Query OK, 0 rows affected (0.32 sec)
```
#### ps_setup_show_disabled
##### Description
Shows all currently disable Performance Schema configuration.
##### Parameters
* in_in_show_instruments (BOOLEAN): Whether to print disabled instruments (can print many items)
* in_in_show_threads (BOOLEAN): Whether to print disabled threads
##### Example
```SQL
mysql> CALL sys.ps_setup_show_disabled(TRUE, TRUE);
+----------------------------+
| performance_schema_enabled |
+----------------------------+
| 1 |
+----------------------------+
1 row in set (0.00 sec)
+--------------------+
| enabled_users |
+--------------------+
| 'mark'@'localhost' |
+--------------------+
1 row in set (0.00 sec)
+-------------+----------------------+---------+-------+
| object_type | objects | enabled | timed |
+-------------+----------------------+---------+-------+
| EVENT | mysql.% | NO | NO |
| EVENT | performance_schema.% | NO | NO |
| EVENT | information_schema.% | NO | NO |
| FUNCTION | mysql.% | NO | NO |
| FUNCTION | performance_schema.% | NO | NO |
| FUNCTION | information_schema.% | NO | NO |
| PROCEDURE | mysql.% | NO | NO |
| PROCEDURE | performance_schema.% | NO | NO |
| PROCEDURE | information_schema.% | NO | NO |
| TABLE | mysql.% | NO | NO |
| TABLE | performance_schema.% | NO | NO |
| TABLE | information_schema.% | NO | NO |
| TRIGGER | mysql.% | NO | NO |
| TRIGGER | performance_schema.% | NO | NO |
| TRIGGER | information_schema.% | NO | NO |
+-------------+----------------------+---------+-------+
15 rows in set (0.00 sec)
+----------------------------------+
| disabled_consumers |
+----------------------------------+
| events_stages_current |
| events_stages_history |
| events_stages_history_long |
| events_statements_history |
| events_statements_history_long |
| events_transactions_history |
| events_transactions_history_long |
| events_waits_current |
| events_waits_history |
| events_waits_history_long |
+----------------------------------+
10 rows in set (0.00 sec)
Empty set (0.00 sec)
+---------------------------------------------------------------------------------------+-------+
| disabled_instruments | timed |
+---------------------------------------------------------------------------------------+-------+
| wait/synch/mutex/sql/TC_LOG_MMAP::LOCK_tc | NO |
| wait/synch/mutex/sql/LOCK_des_key_file | NO |
| wait/synch/mutex/sql/MYSQL_BIN_LOG::LOCK_commit | NO |
...
| memory/sql/servers_cache | NO |
| memory/sql/udf_mem | NO |
| wait/lock/metadata/sql/mdl | NO |
+---------------------------------------------------------------------------------------+-------+
547 rows in set (0.00 sec)
Query OK, 0 rows affected (0.01 sec)
```
#### ps_setup_show_disabled_consumers
##### Description
Shows all currently disabled consumers.
##### Parameters
None
##### Example
```SQL
mysql> CALL sys.ps_setup_show_disabled_consumers();
+---------------------------+
| disabled_consumers |
+---------------------------+
| events_statements_current |
| global_instrumentation |
| thread_instrumentation |
| statements_digest |
+---------------------------+
4 rows in set (0.05 sec)
```
#### ps_setup_show_disabled_instruments
##### Description
Shows all currently disabled instruments.
##### Parameters
None
##### Example
```SQL
mysql> CALL sys.ps_setup_show_disabled_instruments();
```
#### ps_setup_show_enabled
##### Description
Shows all currently enabled Performance Schema configuration.
##### Parameters
* in_show_instruments (BOOLEAN): Whether to print enabled instruments (can print many items)
* in_show_threads (BOOLEAN): Whether to print enabled threads
##### Example
```SQL
mysql> CALL sys.ps_setup_show_enabled(TRUE, TRUE);
+----------------------------+
| performance_schema_enabled |
+----------------------------+
| 1 |
+----------------------------+
1 row in set (0.00 sec)
+---------------+
| enabled_users |
+---------------+
| '%'@'%' |
+---------------+
1 row in set (0.01 sec)
+----------------------+---------+-------+
| objects | enabled | timed |
+----------------------+---------+-------+
| mysql.% | NO | NO |
| performance_schema.% | NO | NO |
| information_schema.% | NO | NO |
| %.% | YES | YES |
+----------------------+---------+-------+
4 rows in set (0.01 sec)
+---------------------------+
| enabled_consumers |
+---------------------------+
| events_statements_current |
| global_instrumentation |
| thread_instrumentation |
| statements_digest |
+---------------------------+
4 rows in set (0.05 sec)
+--------------------------+-------------+
| enabled_threads | thread_type |
+--------------------------+-------------+
| innodb/srv_master_thread | BACKGROUND |
| root@localhost | FOREGROUND |
| root@localhost | FOREGROUND |
| root@localhost | FOREGROUND |
| root@localhost | FOREGROUND |
+--------------------------+-------------+
5 rows in set (0.03 sec)
+-------------------------------------+-------+
| enabled_instruments | timed |
+-------------------------------------+-------+
| wait/io/file/sql/map | YES |
| wait/io/file/sql/binlog | YES |
...
| statement/com/Error | YES |
| statement/com/ | YES |
| idle | YES |
+-------------------------------------+-------+
210 rows in set (0.08 sec)
Query OK, 0 rows affected (0.89 sec)
```
#### ps_setup_show_enabled_consumers
##### Description
Shows all currently enabled consumers.
##### Parameters
None
##### Example
```SQL
mysql> CALL sys.ps_setup_show_enabled_consumers();
+---------------------------+
| enabled_consumers |
+---------------------------+
| events_statements_current |
| global_instrumentation |
| thread_instrumentation |
| statements_digest |
+---------------------------+
4 rows in set (0.05 sec)
```
#### ps_setup_show_enabled_instruments
##### Description
Shows all currently enabled instruments.
##### Parameters
None
##### Example
```SQL
mysql> CALL sys.ps_setup_show_enabled_instruments();
```
#### ps_statement_avg_latency_histogram
##### Description
Outputs a textual histogram graph of the average latency values across all normalized queries tracked within the Performance Schema events_statements_summary_by_digest table.
Can be used to show a very high level picture of what kind of latency distribution statements running within this instance have.
##### Parameters
None.
##### Example
```SQL
mysql> CALL sys.ps_statement_avg_latency_histogram()G
*************************** 1. row ***************************
Performance Schema Statement Digest Average Latency Histogram:
. = 1 unit
* = 2 units
# = 3 units
(0 - 38ms) 240 | ################################################################################
(38 - 77ms) 38 | ......................................
(77 - 115ms) 3 | ...
(115 - 154ms) 62 | *******************************
(154 - 192ms) 3 | ...
(192 - 231ms) 0 |
(231 - 269ms) 0 |
(269 - 307ms) 0 |
(307 - 346ms) 0 |
(346 - 384ms) 1 | .
(384 - 423ms) 1 | .
(423 - 461ms) 0 |
(461 - 499ms) 0 |
(499 - 538ms) 0 |
(538 - 576ms) 0 |
(576 - 615ms) 1 | .
Total Statements: 350; Buckets: 16; Bucket Size: 38 ms;
```
#### ps_trace_statement_digest
##### Description
Traces all instrumentation within Performance Schema for a specific Statement Digest.
When finding a statement of interest within the performance_schema.events_statements_summary_by_digest table, feed the DIGEST MD5 value in to this procedure, set how long to poll for, and at what interval to poll, and it will generate a report of all statistics tracked within Performance Schema for that digest for the interval.
It will also attempt to generate an EXPLAIN for the longest running example of the digest during the interval.
Note this may fail, as Performance Schema truncates long SQL_TEXT values (and hence the EXPLAIN will fail due to parse errors).
Requires the SUPER privilege for "SET sql_log_bin = 0;".
##### Parameters
* in_digest VARCHAR(32): The statement digest identifier you would like to analyze
* in_runtime (INT): The number of seconds to run analysis for (defaults to a minute)
* in_interval (DECIMAL(2,2)): The interval (in seconds, may be fractional) at which to try and take snapshots (defaults to a second)
* in_start_fresh (BOOLEAN): Whether to TRUNCATE the events_statements_history_long and events_stages_history_long tables before starting (default false)
* in_auto_enable (BOOLEAN): Whether to automatically turn on required consumers (default false)
##### Example
```SQL
mysql> call ps_analyze_statement_digest('891ec6860f98ba46d89dd20b0c03652c', 10, 0.1, true, true);
+--------------------+
| SUMMARY STATISTICS |
+--------------------+
| SUMMARY STATISTICS |
+--------------------+
1 row in set (9.11 sec)
+------------+-----------+-----------+-----------+---------------+------------+------------+
| executions | exec_time | lock_time | rows_sent | rows_examined | tmp_tables | full_scans |
+------------+-----------+-----------+-----------+---------------+------------+------------+
| 21 | 4.11 ms | 2.00 ms | 0 | 21 | 0 | 0 |
+------------+-----------+-----------+-----------+---------------+------------+------------+
1 row in set (9.11 sec)
+------------------------------------------+-------+-----------+
| event_name | count | latency |
+------------------------------------------+-------+-----------+
| stage/sql/checking query cache for query | 16 | 724.37 us |
| stage/sql/statistics | 16 | 546.92 us |
| stage/sql/freeing items | 18 | 520.11 us |
| stage/sql/init | 51 | 466.80 us |
...
| stage/sql/cleaning up | 18 | 11.92 us |
| stage/sql/executing | 16 | 6.95 us |
+------------------------------------------+-------+-----------+
17 rows in set (9.12 sec)
+---------------------------+
| LONGEST RUNNING STATEMENT |
+---------------------------+
| LONGEST RUNNING STATEMENT |
+---------------------------+
1 row in set (9.16 sec)
+-----------+-----------+-----------+-----------+---------------+------------+-----------+
| thread_id | exec_time | lock_time | rows_sent | rows_examined | tmp_tables | full_scan |
+-----------+-----------+-----------+-----------+---------------+------------+-----------+
| 166646 | 618.43 us | 1.00 ms | 0 | 1 | 0 | 0 |
+-----------+-----------+-----------+-----------+---------------+------------+-----------+
1 row in set (9.16 sec)
// Truncated for clarity...
+-----------------------------------------------------------------+
| sql_text |
+-----------------------------------------------------------------+
| select hibeventhe0_.id as id1382_, hibeventhe0_.createdTime ... |
+-----------------------------------------------------------------+
1 row in set (9.17 sec)
+------------------------------------------+-----------+
| event_name | latency |
+------------------------------------------+-----------+
| stage/sql/init | 8.61 us |
| stage/sql/Waiting for query cache lock | 453.23 us |
| stage/sql/init | 331.07 ns |
| stage/sql/checking query cache for query | 43.04 us |
...
| stage/sql/freeing items | 30.46 us |
| stage/sql/cleaning up | 662.13 ns |
+------------------------------------------+-----------+
18 rows in set (9.23 sec)
+----+-------------+--------------+-------+---------------+-----------+---------+-------------+------+-------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+--------------+-------+---------------+-----------+---------+-------------+------+-------+
| 1 | SIMPLE | hibeventhe0_ | const | fixedTime | fixedTime | 775 | const,const | 1 | NULL |
+----+-------------+--------------+-------+---------------+-----------+---------+-------------+------+-------+
1 row in set (9.27 sec)
Query OK, 0 rows affected (9.28 sec)
```
#### ps_trace_thread
##### Description
Dumps all data within Performance Schema for an instrumented thread, to create a DOT formatted graph file.
Each resultset returned from the procedure should be used for a complete graph
Requires the SUPER privilege for "SET sql_log_bin = 0;".
##### Parameters
* in_thread_id (INT): The thread that you would like a stack trace for
* in_outfile (VARCHAR(255)): The filename the dot file will be written to
* in_max_runtime (DECIMAL(20,2)): The maximum time to keep collecting data. Use NULL to get the default which is 60 seconds.
* in_interval (DECIMAL(20,2)): How long to sleep between data collections. Use NULL to get the default which is 1 second.
* in_start_fresh (BOOLEAN): Whether to reset all Performance Schema data before tracing.
* in_auto_setup (BOOLEAN): Whether to disable all other threads and enable all consumers/instruments. This will also reset the settings at the end of the run.
* in_debug (BOOLEAN): Whether you would like to include file:lineno in the graph
##### Example
```SQL
mysql> CALL sys.ps_trace_thread(25, CONCAT('/tmp/stack-', REPLACE(NOW(), ' ', '-'), '.dot'), NULL, NULL, TRUE, TRUE, TRUE);
+-------------------+
| summary |
+-------------------+
| Disabled 1 thread |
+-------------------+
1 row in set (0.00 sec)
+---------------------------------------------+
| Info |
+---------------------------------------------+
| Data collection starting for THREAD_ID = 25 |
+---------------------------------------------+
1 row in set (0.03 sec)
+-----------------------------------------------------------+
| Info |
+-----------------------------------------------------------+
| Stack trace written to /tmp/stack-2014-02-16-21:18:41.dot |
+-----------------------------------------------------------+
1 row in set (60.07 sec)
+-------------------------------------------------------------------+
| Convert to PDF |
+-------------------------------------------------------------------+
| dot -Tpdf -o /tmp/stack_25.pdf /tmp/stack-2014-02-16-21:18:41.dot |
+-------------------------------------------------------------------+
1 row in set (60.07 sec)
+-------------------------------------------------------------------+
| Convert to PNG |
+-------------------------------------------------------------------+
| dot -Tpng -o /tmp/stack_25.png /tmp/stack-2014-02-16-21:18:41.dot |
+-------------------------------------------------------------------+
1 row in set (60.07 sec)
+------------------+
| summary |
+------------------+
| Enabled 1 thread |
+------------------+
1 row in set (60.32 sec)
```
#### ps_truncate_all_tables
##### Description
Truncates all summary tables within Performance Schema, resetting all aggregated instrumentation as a snapshot.
##### Parameters
* in_verbose (BOOLEAN): Whether to print each TRUNCATE statement before running
##### Example
```SQL
mysql> CALL sys.ps_truncate_all_tables(false);
+---------------------+
| summary |
+---------------------+
| Truncated 44 tables |
+---------------------+
1 row in set (0.10 sec)
```
#### statement_performance_analyzer
##### Description
Create a report of the statements running on the server.
The views are calculated based on the overall and/or delta activity.
Requires the SUPER privilege for "SET sql_log_bin = 0;".
The following configuration options are supported:
* sys.statement_performance_analyzer.limit
The maximum number of rows to include for the views that does not have a built-in limit (e.g. the 95th percentile view).
If not set the limit is 100.
* sys.statement_performance_analyzer.view
Used together with the 'custom' view. If the value contains a space, it is considered a query, otherwise it must be
an existing view querying the performance_schema.events_statements_summary_by_digest table. There cannot be any limit
clause including in the query or view definition if @sys.statement_performance_analyzer.limit > 0.
If specifying a view, use the same format as for in_table.
* sys.debug
Whether to provide debugging output.
Default is 'OFF'. Set to 'ON' to include.
##### Parameters
* in_action (ENUM('snapshot', 'overall', 'delta', 'create_tmp', 'create_table', 'save', 'cleanup')):
The action to take. Supported actions are:
- snapshot Store a snapshot. The default is to make a snapshot of the current content of
performance_schema.events_statements_summary_by_digest, but by setting in_table
this can be overwritten to copy the content of the specified table.
The snapshot is stored in the sys.tmp_digests temporary table.
- overall Generate analyzis based on the content specified by in_table. For the overall analyzis,
in_table can be NOW() to use a fresh snapshot. This will overwrite an existing snapshot.
Use NULL for in_table to use the existing snapshot. If in_table IS NULL and no snapshot
exists, a new will be created.
See also in_views and @sys.statement_performance_analyzer.limit.
- delta Generate a delta analysis. The delta will be calculated between the reference table in
in_table and the snapshot. An existing snapshot must exist.
The action uses the sys.tmp_digests_delta temporary table.
See also in_views and @sys.statement_performance_analyzer.limit.
- create_table Create a regular table suitable for storing the snapshot for later use, e.g. for
calculating deltas.
- create_tmp Create a temporary table suitable for storing the snapshot for later use, e.g. for
calculating deltas.
- save Save the snapshot in the table specified by in_table. The table must exists and have
the correct structure.
If no snapshot exists, a new is created.
- cleanup Remove the temporary tables used for the snapshot and delta.
* in_table (VARCHAR(129)):
The table argument used for some actions. Use the format 'db1.t1' or 't1' without using any backticks (`)
for quoting. Periods (.) are not supported in the database and table names.
The meaning of the table for each action supporting the argument is:
- snapshot The snapshot is created based on the specified table. Set to NULL or NOW() to use
the current content of performance_schema.events_statements_summary_by_digest.
- overall The table with the content to create the overall analyzis for. The following values
can be used:
- A table name - use the content of that table.
- NOW() - create a fresh snapshot and overwrite the existing snapshot.
- NULL - use the last stored snapshot.
- delta The table name is mandatory and specified the reference view to compare the currently
stored snapshot against. If no snapshot exists, a new will be created.
- create_table The name of the regular table to create.
- create_tmp The name of the temporary table to create.
- save The name of the table to save the currently stored snapshot into.
* in_views (SET ('with_runtimes_in_95th_percentile', 'analysis', 'with_errors_or_warnings',
'with_full_table_scans', 'with_sorting', 'with_temp_tables', 'custom'))
Which views to include:
- with_runtimes_in_95th_percentile Based on the sys.statements_with_runtimes_in_95th_percentile view
- analysis Based on the sys.statement_analysis view
- with_errors_or_warnings Based on the sys.statements_with_errors_or_warnings view
- with_full_table_scans Based on the sys.statements_with_full_table_scans view
- with_sorting Based on the sys.statements_with_sorting view
- with_temp_tables Based on the sys.statements_with_temp_tables view
- custom Use a custom view. This view must be specified in @sys.statement_performance_analyzer.view to an existing view or a query
Default is to include all except 'custom'.
##### Example
```SQL
-- To create a report with the queries in the 95th percentile since last truncate of performance_schema.events_statements_summary_by_digest and the delta for a 1 minute period:
--
-- 1. Create a temporary table to store the initial snapshot.
-- 2. Create the initial snapshot.
-- 3. Save the initial snapshot in the temporary table.
-- 4. Wait one minute.
-- 5. Create a new snapshot.
-- 6. Perform analyzis based on the new snapshot.
-- 7. Perform analyzis based on the delta between the initial and new snapshots.
mysql> CALL sys.statement_performance_analyzer('create_tmp', 'mydb.tmp_digests_ini', NULL);
Query OK, 0 rows affected (0.08 sec)
mysql> CALL sys.statement_performance_analyzer('snapshot', NULL, NULL);
Query OK, 0 rows affected (0.02 sec)
mysql> CALL sys.statement_performance_analyzer('save', 'mydb.tmp_digests_ini', NULL);
Query OK, 0 rows affected (0.00 sec)
mysql> DO SLEEP(60);
Query OK, 0 rows affected (1 min 0.00 sec)
mysql> CALL sys.statement_performance_analyzer('snapshot', NULL, NULL);
Query OK, 0 rows affected (0.02 sec)
mysql> CALL sys.statement_performance_analyzer('overall', NULL, 'with_runtimes_in_95th_percentile');
+-----------------------------------------+
| Next Output |
+-----------------------------------------+
| Queries with Runtime in 95th Percentile |
+-----------------------------------------+
1 row in set (0.05 sec)
...
mysql> CALL sys.statement_performance_analyzer('delta', 'mydb.tmp_digests_ini', 'with_runtimes_in_95th_percentile');
+-----------------------------------------+
| Next Output |
+-----------------------------------------+
| Queries with Runtime in 95th Percentile |
+-----------------------------------------+
1 row in set (0.03 sec)
...
-- To create an overall report of the 95th percentile queries and the top 10 queries with full table scans:
mysql> CALL sys.statement_performance_analyzer('snapshot', NULL, NULL);
Query OK, 0 rows affected (0.01 sec)
mysql> SET @sys.statement_performance_analyzer.limit = 10;
Query OK, 0 rows affected (0.00 sec)
mysql> CALL sys.statement_performance_analyzer('overall', NULL, 'with_runtimes_in_95th_percentile,with_full_table_scans');
+-----------------------------------------+
| Next Output |
+-----------------------------------------+
| Queries with Runtime in 95th Percentile |
+-----------------------------------------+
1 row in set (0.01 sec)
...
+-------------------------------------+
| Next Output |
+-------------------------------------+
| Top 10 Queries with Full Table Scan |
+-------------------------------------+
1 row in set (0.09 sec)
...
-- Use a custom view showing the top 10 query sorted by total execution time refreshing the view every minute using
-- the watch command in Linux.
mysql> CREATE OR REPLACE VIEW mydb.my_statements AS
-> SELECT sys.format_statement(DIGEST_TEXT) AS query,
-> SCHEMA_NAME AS db,
-> COUNT_STAR AS exec_count,
-> sys.format_time(SUM_TIMER_WAIT) AS total_latency,
-> sys.format_time(AVG_TIMER_WAIT) AS avg_latency,
-> ROUND(IFNULL(SUM_ROWS_SENT / NULLIF(COUNT_STAR, 0), 0)) AS rows_sent_avg,
-> ROUND(IFNULL(SUM_ROWS_EXAMINED / NULLIF(COUNT_STAR, 0), 0)) AS rows_examined_avg,
-> ROUND(IFNULL(SUM_ROWS_AFFECTED / NULLIF(COUNT_STAR, 0), 0)) AS rows_affected_avg,
-> DIGEST AS digest
-> FROM performance_schema.events_statements_summary_by_digest
-> ORDER BY SUM_TIMER_WAIT DESC;
Query OK, 0 rows affected (0.01 sec)
mysql> CALL sys.statement_performance_analyzer('create_table', 'mydb.digests_prev', NULL);
Query OK, 0 rows affected (0.10 sec)
shell$ watch -n 60 "mysql sys --table -e \"
> SET @sys.statement_performance_analyzer.view = 'mydb.my_statements';
> SET @sys.statement_performance_analyzer.limit = 10;
> CALL statement_performance_analyzer('snapshot', NULL, NULL);
> CALL statement_performance_analyzer('delta', 'mydb.digests_prev', 'custom');
> CALL statement_performance_analyzer('save', 'mydb.digests_prev', NULL);
> \""
Every 60.0s: mysql sys --table -e " ... Mon Dec 22 10:58:51 2014
+----------------------------------+
| Next Output |
+----------------------------------+
| Top 10 Queries Using Custom View |
+----------------------------------+
+-------------------+-------+------------+---------------+-------------+---------------+-------------------+-------------------+----------------------------------+
| query | db | exec_count | total_latency | avg_latency | rows_sent_avg | rows_examined_avg | rows_affected_avg | digest |
+-------------------+-------+------------+---------------+-------------+---------------+-------------------+-------------------+----------------------------------+
...
```
#### table_exists
##### Description
Tests whether the table specified in in_db and in_table exists either as a regular
table, or as a temporary table. The returned value corresponds to the table that
will be used, so if there's both a temporary and a permanent table with the given
name, then 'TEMPORARY' will be returned.
##### Parameters
* in_db (VARCHAR(64)): The database name to check for the existance of the table in.
* in_table (VARCHAR(64)): The name of the table to check the existance of.
* out_exists ENUM('', 'BASE TABLE', 'VIEW', 'TEMPORARY'): The return value: whether the table exists. The value is one of:
- '' - the table does not exist neither as a base table, view, nor temporary table.
- 'BASE TABLE' - the table name exists as a permanent base table table.
- 'VIEW' - the table name exists as a view.
- 'TEMPORARY' - the table name exists as a temporary table.
##### Example
```SQL
mysql> CREATE DATABASE db1;
Query OK, 1 row affected (0.07 sec)
mysql> use db1;
Database changed
mysql> CREATE TABLE t1 (id INT PRIMARY KEY);
Query OK, 0 rows affected (0.08 sec)
mysql> CREATE TABLE t2 (id INT PRIMARY KEY);
Query OK, 0 rows affected (0.08 sec)
mysql> CREATE view v_t1 AS SELECT * FROM t1;
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TEMPORARY TABLE t1 (id INT PRIMARY KEY);
Query OK, 0 rows affected (0.00 sec)
mysql> CALL sys.table_exists('db1', 't1', @exists); SELECT @exists;
Query OK, 0 rows affected (0.00 sec)
+------------+
| @exists |
+------------+
| TEMPORARY |
+------------+
1 row in set (0.00 sec)
mysql> CALL sys.table_exists('db1', 't2', @exists); SELECT @exists;
Query OK, 0 rows affected (0.00 sec)
+------------+
| @exists |
+------------+
| BASE TABLE |
+------------+
1 row in set (0.01 sec)
mysql> CALL sys.table_exists('db1', 'v_t1', @exists); SELECT @exists;
Query OK, 0 rows affected (0.00 sec)
+---------+
| @exists |
+---------+
| VIEW |
+---------+
1 row in set (0.00 sec)
mysql> CALL sys.table_exists('db1', 't3', @exists); SELECT @exists;
Query OK, 0 rows affected (0.01 sec)
+---------+
| @exists |
+---------+
| |
+---------+
1 row in set (0.00 sec)
```