from: http://mysqlserverteam.com/the-mysql-sys-schema-in-mysql-5-7-7/
mysql 5.7 提供一个 SYS Schema,从这里面可以查 内存page、io、lock、latency等各种状态信息，为性能调优提供重要的依据。更详细，可以看看https://github.com/MarkLeith/mysql-sys/blob/master/README.md
举例，查找2个query 发生lock 争用的详情:
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
简单介绍见下文：
New in MySQL 5.7.7, the MySQL sys schema (originally the ps_helper project) is now included by default within the MySQL server!
For those unfamiliar with the sys schema project, it is a database schema with a set of objects (views, stored procedures, stored functions, and table with a couple of triggers on it) that were implemented to give easy, human readable, DBA and Developer based use case access to the wealth of instrumentation data implemented primarily withinPerformance Schema, but also with various INFORMATION_SCHEMA tables as well.
First, what does included by default mean?
It means that when you initialize your MySQL 5.7 server for the first time, with eithermysql_install_db, or the new mysqld --initialize option, the sys schema is added alongside the other standard schemas, nothing further for you to do, just initialize your database instance as you normally would.
When upgrading from a previous version, and running mysql_upgrade, the instance is checked to see whether the sys schema already exists or not, and creates or upgrades the schema appropriately. The version of the sys schema bundled with 5.7.7 is 1.4.0, so if you already have that version installed, mysql_ugprade will do nothing. However, if you have a version prior to that, mysql_upgrade will re-create the schema with the updated version:
|
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11
12
13
14
15
16
|
$
/
opt
/
mysql
/
5.7.7
/
bin
/
mysql_upgrade
-
u
root
-
p
-
h
127.0.0.1
-
P
5707
Enter
password
:
Checking
if
update
is
needed
.
Checking
server
version
.
Running
queries
to
upgrade
MySQL
server
.
Checking
system
database
.
mysql
.columns_priv
OK
.
.
.snip
.
.
.
mysql
.user
OK
Found
outdated
sys
schema
version
1.3.0.
Upgrading
the
sys
schema
.
Checking
databases
.
sys
.sys_config
OK
Upgrade
process
completed
successfully
.
Checking
if
update
is
needed
.
$
|
If the sys schema exists on upgrade, but the sys.version view does not exist, thenmysql_upgrade will return an error, as it will assume that the sys schema that is within the instance is a user created schema:
|
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2
3
4
5
6
7
8
9
10
|
$
/
opt
/
mysql
/
5.7.7
/
bin
/
mysql_upgrade
-
u
root
-
p
-
h
127.0.0.1
-
P
5707
Enter
password
:
Checking
if
update
is
needed
.
Checking
server
version
.
Running
queries
to
upgrade
MySQL
server
.
Checking
system
database
.
mysql
.columns_priv
OK
.
.
.snip
.
.
.
mysql
.user
OK
Error
occurred
:
A
sys
schema
exists
with
no
sys
.version
view
.
If
you
have
a
user
created
sys
schema
,
this
must
be
renamed
for
the
upgrade
to
succeed
.
|
If you already have a schema called sys when upgrading to version 5.7.7 or later, you should ensure that it is renamed before running mysql_upgrade.
If you want to skip creating the sys schema with either mysql_install_db or mysql_upgrade, you can use the new --skip-sys-schema option. You can always install it by hand at later time, using the $install_dir/share/mysql_sys_schema.sql file laid down with each installation (though this is not used within any of the above options, the DDL statements are compiled in for those).
After installation or upgrade, you then get access to the objects within the sys schema, enabling you to dive deeper in to the statistics needed to be able to answer some of the questions you get, or problems that you have to solve, on a day to day basis.
Questions like “Who is taking up all the resources on my database server?” can be quickly and easily answered with either the user summary views:
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49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
mysql
>
show
tables
like
'user%'
;
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
-
+
|
Tables_in_sys
(
user
%
)
|
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
-
+
|
user_summary
|
|
user_summary_by_file_io
|
|
user_summary_by_file_io_type
|
|
user_summary_by_stages
|
|
user_summary_by_statement_latency
|
|
user_summary_by_statement_type
|
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
-
+
6
rows
in
set
(
0.00
sec
)
mysql
>
select *
from
user_summary
\
G
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
1.
row *
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
user
:
msandbox
statements
:
5971
statement_latency
:
1.20
m
statement_avg_latency
:
12.04
ms
table_scans
:
193
file_ios
:
53784
file_io_latency
:
15.35
m
current_connections
:
1
total_connections
:
8
unique_hosts
:
1
current_memory
:
314.80
KiB
total_memory_allocated
:
14.85
MiB
.
.
.
mysql
>
select *
from
user_summary_by_file_io_type
where
user
=
'msandbox'
;
+
--
--
--
--
--
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
+
--
--
--
-
+
--
--
--
--
--
-
+
--
--
--
--
--
--
-
+
|
user
|
event_name
|
total
|
latency
|
max_latency
|
+
--
--
--
--
--
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
+
--
--
--
-
+
--
--
--
--
--
-
+
--
--
--
--
--
--
-
+
|
msandbox
|
wait
/
io
/
file
/
sql
/
FRM
|
36929
|
21.95
s
|
239.56
ms
|
|
msandbox
|
wait
/
io
/
file
/
sql
/
file_parser
|
1266
|
4.44
s
|
250.93
ms
|
|
msandbox
|
wait
/
io
/
file
/
innodb
/
innodb_data_file
|
1086
|
1.35
s
|
647.00
ms
|
|
msandbox
|
wait
/
io
/
file
/
csv
/
metadata
|
124
|
1.15
s
|
192.03
ms
|
|
msandbox
|
wait
/
io
/
file
/
myisam
/
kfile
|
4376
|
221.53
ms
|
23.71
ms
|
|
msandbox
|
wait
/
io
/
file
/
innodb
/
innodb_log_file
|
274
|
68.37
ms
|
14.65
ms
|
|
msandbox
|
wait
/
io
/
file
/
myisam
/
dfile
|
3544
|
56.23
ms
|
6.66
ms
|
|
msandbox
|
wait
/
io
/
file
/
csv
/
data
|
56
|
9.90
ms
|
1.91
ms
|
|
msandbox
|
wait
/
io
/
file
/
sql
/
trigger
|
2
|
3.86
ms
|
3.77
ms
|
|
msandbox
|
wait
/
io
/
file
/
archive
/
data
|
349
|
2.58
ms
|
27.89
us
|
|
msandbox
|
wait
/
io
/
file
/
sql
/
dbopt
|
14
|
601.64
us
|
117.95
us
|
|
msandbox
|
wait
/
io
/
file
/
sql
/
misc
|
13
|
540.14
us
|
69.84
us
|
+
--
--
--
--
--
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
+
--
--
--
-
+
--
--
--
--
--
-
+
--
--
--
--
--
--
-
+
12
rows
in
set
(
0.01
sec
)
mysql
>
select *
from
user_summary_by_statement_type
where
user
=
'msandbox'
;
+
--
--
--
--
--
+
--
--
--
--
--
--
--
--
--
-
+
--
--
--
-
+
--
--
--
--
--
--
--
-
+
--
--
--
--
--
--
-
+
--
--
--
--
--
--
--
+
--
--
--
--
--
-
+
--
--
--
--
--
--
--
-
+
--
--
--
--
--
--
--
-
+
--
--
--
--
--
--
+
|
user
|
statement
|
total
|
total_latency
|
max_latency
|
lock_latency
|
rows_sent
|
rows_examined
|
rows_affected
|
full_scans
|
+
--
--
--
--
--
+
--
--
--
--
--
--
--
--
--
-
+
--
--
--
-
+
--
--
--
--
--
--
--
-
+
--
--
--
--
--
--
-
+
--
--
--
--
--
--
--
+
--
--
--
--
--
-
+
--
--
--
--
--
--
--
-
+
--
--
--
--
--
--
--
-
+
--
--
--
--
--
--
+
|
msandbox
|
alter_table
|
262
|
28.87
s
|
1.54
s
|
22.56
s
|
0
|
0
|
640
|
0
|
|
msandbox
|
execute_sql
|
398
|
23.63
s
|
339.61
ms
|
0
ps
|
0
|
0
|
176
|
0
|
|
msandbox
|
create_view
|
92
|
15.88
s
|
429.34
ms
|
253.04
ms
|
0
|
0
|
0
|
0
|
|
msandbox
|
create_trigger
|
2
|
607.76
ms
|
314.93
ms
|
1.30
ms
|
0
|
0
|
0
|
0
|
|
msandbox
|
select
|
119
|
574.95
ms
|
221.74
ms
|
74.07
ms
|
2628
|
14354
|
0
|
68
|
|
msandbox
|
check
|
63
|
543.44
ms
|
286.57
ms
|
540.43
ms
|
0
|
0
|
0
|
0
|
|
msandbox
|
drop_view
|
1
|
377.27
ms
|
377.27
ms
|
0
ps
|
0
|
0
|
0
|
0
|
|
msandbox
|
show_tables
|
17
|
280.49
ms
|
59.88
ms
|
1.39
ms
|
1000
|
1000
|
0
|
17
|
|
msandbox
|
drop_trigger
|
2
|
250.50
ms
|
137.91
ms
|
16.32
ms
|
0
|
0
|
0
|
0
|
|
msandbox
|
set_option
|
842
|
230.43
ms
|
34.36
ms
|
2.24
ms
|
0
|
178
|
0
|
12
|
|
msandbox
|
Field
List
|
367
|
216.27
ms
|
42.25
ms
|
62.14
ms
|
0
|
0
|
0
|
0
|
.
.
.
|
Or similar output with “Which hosts are hitting my database server those most?” and these tables:
|
1
2
3
4
5
6
7
8
9
10
11
12
|
mysql
>
show
tables
like
'host%'
;
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
-
+
|
Tables_in_sys
(
host
%
)
|
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
-
+
|
host_summary
|
|
host_summary_by_file_io
|
|
host_summary_by_file_io_type
|
|
host_summary_by_stages
|
|
host_summary_by_statement_latency
|
|
host_summary_by_statement_type
|
+
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
-
+
6
rows
in
set
(
0.04
sec
)
|
Maybe you are ask yourself “Which objects are accessed the most, and how?”:
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
mysql
>
select
*
from
sys.schema_table_statistics
limit
5\G
***************************
1.
row
***************************
table_schema:
mem__quan
table_name:
normalized_statements_by_server_by_schema
total_latency:
1.01
m
rows_fetched:
8171
fetch_latency:
321.97
ms
rows_inserted:
9524
insert_latency:
58.24
s
rows_updated:
8171
update_latency:
2.16
s
rows_deleted:
0
delete_latency:
0
ps
io_read_requests:
37
io_read:
57.82
KiB
io_read_latency:
86.55
ms
io_write_requests:
354
io_write:
3.99
MiB
io_write_latency:
2.40
ms
io_misc_requests:
140
io_misc_latency:
500.78
ms
***************************
2.
row
***************************
table_schema:
mem__quan
table_name:
normalized_statements_by_server_by_schema_data
total_latency:
39.88
s
rows_fetched:
285
fetch_latency:
86.42
ms
rows_inserted:
8848
insert_latency:
39.01
s
rows_updated:
261
update_latency:
786.48
ms
rows_deleted:
0
delete_latency:
0
ps
io_read_requests:
38
io_read:
66.58
KiB
io_read_latency:
114.21
ms
io_write_requests:
1210
io_write:
20.48
MiB
io_write_latency:
160.15
ms
io_misc_requests:
196
io_misc_latency:
893.47
ms
...
|
Or “What statements have the highest overall latency, and what statistics did they have?”
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
mysql
>
select
*
from
statement_analysis
limit
10\G
***************************
1.
row
***************************
query:
SELECT
`t`
.
`THREAD_ID`
AS
`t
...
_NUMBER_OF_BYTES_USED`
)
DESC
db:
NULL
full_scan:
*
exec_count:
20835
err_count:
4
warn_count:
0
total_latency:
38.96
m
max_latency:
1.84
s
avg_latency:
112.21
ms
lock_latency:
33.91
s
rows_sent:
844
rows_sent_avg:
0
rows_examined:
216255376
rows_examined_avg:
10379
rows_affected:
0
rows_affected_avg:
0
tmp_tables:
83340
tmp_disk_tables:
41666
rows_sorted:
1419984
sort_merge_passes:
0
digest:
2a8440817e00ec634e3d0b88c8e85ca4
first_seen:
2015
-04
-10
10:23:49
last_seen:
2015
-04
-10
11:11:49
***************************
2.
row
***************************
query:
SELECT
*
FROM
(
SELECT
digest
...
_used
AS
`noIndexUsedCount`
,
db:
mysql
full_scan:
*
exec_count:
221
err_count:
0
warn_count:
73
total_latency:
30.09
m
max_latency:
37.49
s
avg_latency:
8.17
s
lock_latency:
247.86
ms
rows_sent:
43101
rows_sent_avg:
195
rows_examined:
31818247
rows_examined_avg:
143974
rows_affected:
0
rows_affected_avg:
0
tmp_tables:
663
tmp_disk_tables:
0
rows_sorted:
1555
sort_merge_passes:
0
digest:
ef667dfa3f6169ffdecfd9ffb87cd10c
first_seen:
2015
-04
-09
16:59:14
last_seen:
2015
-04
-10
12:57:21
|
Or “Which statements are using temporary tables on disk?”
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
mysql
>
select
*
from
statements_with_temp_tables
limit
5\G;
***************************
1.
row
***************************
query:
SELECT
`r`
.
`trx_wait_started
...
ode`
,
`b`
.
`trx_started`
AS
db:
NULL
exec_count:
478707
total_latency:
13.43
m
memory_tmp_tables:
3350949
disk_tmp_tables:
957414
avg_tmp_tables_per_query:
7
tmp_tables_to_disk_pct:
29
first_seen:
2015
-04
-10
09:49:18
last_seen:
2015
-04
-10
13:12:36
digest:
529f34e4046a3f19b7023aca37d6a394
***************************
2.
row
***************************
query:
SELECT
`t`
.
`THREAD_ID`
AS
`t
...
_NUMBER_OF_BYTES_USED`
)
DESC
db:
NULL
exec_count:
20835
total_latency:
38.96
m
memory_tmp_tables:
83340
disk_tmp_tables:
41666
avg_tmp_tables_per_query:
4
tmp_tables_to_disk_pct:
50
first_seen:
2015
-04
-10
10:23:49
last_seen:
2015
-04
-10
11:11:49
digest:
2a8440817e00ec634e3d0b88c8e85ca4
...
|
Or “Which tables take the most space in my InnoDB buffer pool?”
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
|
mysql
>
select
*
from
innodb_buffer_stats_by_table
limit
10;
+-------------------+----------------------------------------------------+------------+------------+-------+--------------+-----------+-------------+
|
object_schema
|
object_name
|
allocated
|
data
|
pages
|
pages_hashed
|
pages_old
|
rows_cached
|
+-------------------+----------------------------------------------------+------------+------------+-------+--------------+-----------+-------------+
|
mem__quan
|
normalized_statements_by_server_by_schema_data
|
8.39
MiB
|
10.87
MiB
|
1074
|
1074
|
1074
|
36995
|
|
InnoDB
System
|
SYS_TABLES
|
1.70
MiB
|
1.43
MiB
|
109
|
109
|
109
|
4656
|
|
mem__advisor_text
|
localized_text
|
1.45
MiB
|
1.11
MiB
|
93
|
93
|
93
|
1514
|
|
mysql
|
innodb_index_stats
|
784.00
KiB
|
380.36
KiB
|
49
|
49
|
49
|
3182
|
|
mem__instruments
|
globaleventwaitsfilesummaryadvisor_fileioeventdata
|
600.00
KiB
|
792.25
KiB
|
75
|
75
|
75
|
2265
|
|
mem__quan
|
example_statements
|
560.00
KiB
|
550.59
KiB
|
70
|
70
|
70
|
1414
|
|
mem__bean_config
|
serialized_states
|
480.00
KiB
|
190.83
KiB
|
30
|
30
|
30
|
481
|
|
mem__events
|
events
|
320.00
KiB
|
216.23
KiB
|
20
|
20
|
20
|
169
|
|
InnoDB
System
|
SYS_COLUMNS
|
288.00
KiB
|
203.33
KiB
|
18
|
18
|
18
|
3055
|
|
mem__quan
|
normalized_statements
|
288.00
KiB
|
355.21
KiB
|
36
|
36
|
36
|
716
|
+-------------------+----------------------------------------------------+------------+------------+-------+--------------+-----------+-------------+
10
rows
in
set
(0.22
sec)
|
“Where is all the memory going on my instance?”
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
|
mysql
>
select
*
from
memory_global_by_current_bytes
limit
10;
+-----------------------------------------------------------------------------+---------------+---------------+-------------------+------------+------------+----------------+
|
event_name
|
current_count
|
current_alloc
|
current_avg_alloc
|
high_count
|
high_alloc
|
high_avg_alloc
|
+-----------------------------------------------------------------------------+---------------+---------------+-------------------+------------+------------+----------------+
|
memory
/
innodb
/buf_buf_pool
|
1
|
131.06
MiB
|
131.06
MiB
|
1
|
131.06
MiB
|
131.06
MiB
|
|
memory
/
innodb
/mem0mem
|
12476
|
17.17
MiB
|
1.41
KiB
|
13197
|
32.27
MiB
|
2.50
KiB
|
|
memory
/
innodb
/log0log
|
9
|
16.01
MiB
|
1.78
MiB
|
9
|
16.01
MiB
|
1.78
MiB
|
|
memory
/
innodb
/lock0lock
|
9279
|
14.41
MiB
|
1.59
KiB
|
9279
|
14.41
MiB
|
1.59
KiB
|
|
memory
/performance_schema
/events_statements_history_long
|
1
|
13.50
MiB
|
13.50
MiB
|
1
|
13.50
MiB
|
13.50
MiB
|
|
memory
/performance_schema
/events_statements_summary_by_digest.tokens
|
1
|
9.77
MiB
|
9.77
MiB
|
1
|
9.77
MiB
|
9.77
MiB
|
|
memory
/performance_schema
/events_statements_history_long.sqltext
|
1
|
9.77
MiB
|
9.77
MiB
|
1
|
9.77
MiB
|
9.77
MiB
|
|
memory
/performance_schema
/events_statements_history_long.tokens
|
1
|
9.77
MiB
|
9.77
MiB
|
1
|
9.77
MiB
|
9.77
MiB
|
|
memory
/performance_schema
/table_handles
|
1
|
9.00
MiB
|
9.00
MiB
|
1
|
9.00
MiB
|
9.00
MiB
|
|
memory
/performance_schema
/events_statements_summary_by_thread_by_event_name
|
1
|
8.58
MiB
|
8.58
MiB
|
1
|
8.58
MiB
|
8.58
MiB
|
+-----------------------------------------------------------------------------+---------------+---------------+-------------------+------------+------------+----------------+
|
“Which database files cause the most IO, and what kind of IO pattern do they have?”
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
|
mysql
>
select
*
from
io_global_by_file_by_latency
limit
10;
+-----------------------------------------------------------------------------------+---------+---------------+------------+--------------+-------------+---------------+------------+--------------+
|
file
|
total
|
total_latency
|
count_read
|
read_latency
|
count_write
|
write_latency
|
count_misc
|
misc_latency
|
+-----------------------------------------------------------------------------------+---------+---------------+------------+--------------+-------------+---------------+------------+--------------+
|
@@datadir
/ib_logfile0
|
70001
|
57.67
s
|
4
|
12.47
us
|
35507
|
3.59
s
|
34490
|
54.08
s
|
|
@@datadir
/ibdata1
|
37512
|
37.15
s
|
715
|
1.14
s
|
32690
|
623.45
ms
|
4107
|
35.38
s
|
|
@@datadir
/ib_logfile1
|
46994
|
24.88
s
|
2
|
18.75
ms
|
23495
|
399.44
ms
|
23497
|
24.47
s
|
|
@@datadir
/mysql
/proc.MYD
|
3072639
|
14.14
s
|
2048438
|
12.02
s
|
7
|
217.13
us
|
1024194
|
2.11
s
|
|
@@datadir
/mem__quan
/normalized_statements_by_server_by_schema_data.ibd
|
3134
|
2.59
s
|
7
|
31.52
ms
|
2793
|
397.90
ms
|
334
|
2.16
s
|
|
@@datadir
/mem__instruments
/globaleventwaitsfilesummaryadvisor_fileioeventdata.ibd
|
778
|
1.50
s
|
10
|
10.37
ms
|
629
|
272.66
ms
|
139
|
1.22
s
|
|
@@datadir
/mem__instruments
/networktrafficadvisor_networktraffic.ibd
|
424
|
1.30
s
|
15
|
1.09
ms
|
337
|
351.11
ms
|
72
|
945.82
ms
|
|
@@datadir
/mem__instruments
/fsstatistics.ibd
|
397
|
1.21
s
|
9
|
11.39
ms
|
328
|
44.60
ms
|
60
|
1.15
s
|
|
@@datadir
/mem__events
/
events.ibd
|
1518
|
1.15
s
|
15
|
6.11
ms
|
1292
|
11.03
ms
|
211
|
1.14
s
|
|
@@datadir
/mem__inventory
/httpserver.ibd
|
158
|
588.31
ms
|
6
|
906.05
us
|
98
|
650.16
us
|
54
|
586.76
ms
|
+-----------------------------------------------------------------------------------+---------+---------------+------------+--------------+-------------+---------------+------------+--------------+
|
“Where is the time being spent the most within my instance?”
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
|
mysql
(5.7.8)
>
select
*
from
waits_global_by_latency
limit
20;
+----------------------------------------------+----------+---------------+-------------+-------------+
|
events
|
total
|
total_latency
|
avg_latency
|
max_latency
|
+----------------------------------------------+----------+---------------+-------------+-------------+
|
wait
/io
/
table
/
sql
/
handler
|
651645
|
7.54
m
|
694.20
us
|
2.31
s
|
|
wait
/io
/
socket
/
sql
/client_connection
|
8171190
|
3.74
m
|
27.44
us
|
215.29
ms
|
|
wait
/synch
/sxlock
/
innodb
/dict_operation_lock
|
270734
|
1.60
m
|
354.35
us
|
1.21
s
|
|
wait
/io
/
file
/
innodb
/innodb_log_file
|
118289
|
1.40
m
|
707.62
us
|
820.19
ms
|
|
wait
/io
/
file
/
innodb
/innodb_data_file
|
82271
|
1.19
m
|
869.42
us
|
2.98
s
|
|
wait
/synch
/mutex
/
innodb
/log_sys_mutex
|
4154064
|
37.93
s
|
9.13
us
|
238.31
ms
|
|
wait
/synch
/mutex
/
sql
/LOCK_table_cache
|
4239803
|
35.55
s
|
8.38
us
|
13.47
ms
|
|
wait
/synch
/sxlock
/
innodb
/index_tree_rw_lock
|
2447691
|
27.68
s
|
11.31
us
|
228.94
ms
|
|
wait
/synch
/mutex
/
innodb
/buf_pool_mutex
|
3465947
|
18.26
s
|
5.27
us
|
2.31
s
|
|
wait
/synch
/mutex
/
innodb
/dict_sys_mutex
|
1104503
|
15.95
s
|
14.44
us
|
1.18
s
|
|
wait
/io
/
file
/
myisam
/dfile
|
3185357
|
14.69
s
|
4.61
us
|
130.09
ms
|
|
wait
/io
/
file
/
sql
/FRM
|
26965
|
13.40
s
|
497.05
us
|
96.99
ms
|
|
wait
/synch
/mutex
/
innodb
/trx_sys_mutex
|
5830470
|
10.92
s
|
1.87
us
|
83.22
ms
|
|
wait
/synch
/mutex
/
innodb
/lock_mutex
|
1015659
|
6.13
s
|
6.03
us
|
81.22
ms
|
|
wait
/synch
/sxlock
/
innodb
/checkpoint_lock
|
2036
|
5.19
s
|
2.55
ms
|
355.62
ms
|
|
wait
/synch
/sxlock
/
innodb
/fil_space_latch
|
7061817
|
4.85
s
|
686.52
ns
|
528.87
ms
|
|
wait
/synch
/mutex
/
sql
/THD::LOCK_thd_data
|
37813109
|
4.08
s
|
107.82
ns
|
29.66
ms
|
|
wait
/synch
/sxlock
/
innodb
/btr_search_latch
|
451144
|
3.78
s
|
8.39
us
|
27.38
ms
|
|
wait
/synch
/mutex
/
innodb
/fil_system_mutex
|
12971063
|
2.79
s
|
215.27
ns
|
32.92
ms
|
|
wait
/io
/
socket
/
sql
/server_unix_socket
|
275681
|
2.03
s
|
7.35
us
|
7.39
ms
|
+----------------------------------------------+----------+---------------+-------------+-------------+
|
Now you can answer all of these questions, and many more, with ease.
The reference documentation for sys is currently being worked on (it’s a huge job), but in the mean time, if you want to see the full power of what you get from the sys schema bundled within MySQL 5.7.7, see the README on the GitHub project.
Try it out, and give us your feedback! If you spot any bugs, please report them on http://bugs.mysql.com/ under the new “MySQL Server: SYS Schema” category.