1 issue
- How to determine whether the server has reached its best performance
- Find out why the execution of a statement is not fast enough
- Some intermittent fault difficult
2 Introduction to Performance Optimization
性能: A measure of time to complete the tasks required for a
The purpose of the database server to execute SQL statements, so it is concerned about the type of mission statements and other inquiries, such as SELETE, UPDATE, DELETE and so on.
优化: Under certain workloads to reduce response time as possible.
If the performance optimization as merely improve query per second, which is actually optimize throughput, performance is optimized sub-products.
Throughput: the number of queries per unit time, is the reciprocal of the definition of performance.
2.1 by optimizing the performance analysis
Once you learn and practice 面向响应时间optimization methods, you will need to constantly find the system performance analysis (profiling).
Performance analysis is the 测量和分析时间花费在哪里main method. Performance analysis is generally divided into two steps: 测量任务所花费的时间before 对结果进行统计和排序，将重要的任务排在前面.
Two types of performance analysis: 基于执行时间的分析and 基于等待的分析.
2.2 understand the performance analysis
Three pairs of application performance analysis
4 MySQL query analysis
4.1 server load analysis
Capture MySQL queries to a log file
Query log analysis
4.2 dissect a single query
Use SHOW PROFILE
Use SHOW STATUS
The slow query log
Use Performance Schema
4.3 Performance analysis
5 diagnose intermittent problems
5.1 single query server problem or issue
Use SHOW GLOBAL STATUS
Use SHOW PROCESSLIST
Use Query Log
Understand the problems found
5.2 capture diagnostic data
Diagnosis Trigger
What kind of data to be collected
Interpretation of results data
5.3 Diagnosis of a case
6 other analysis tools
Table 6.1 Use USER_STATISTICS
6.2 strace
7 summary
