•The mysqlslap  program can be helpful for simulating a high load produced by multiple clients issuing queries simultaneously. See Section 4.5.8, “mysqlslap — A Load Emulation Client” . 

•You can also try benchmarking packages such as SysBench and DBT2, available at https:// launchpad.net/sysbench, and http://osdldbt.sourceforge.net/#dbt2. 

These programs or packages can bring a system to its knees, so be sure to use them only on your development systems. 

## 8.13.3 Measuring Performance with performance_schema 

You can query the tables in the performance_schema  database to see real-time information about the performance characteristics of your server and the applications it is running. See Chapter 27, MySQL Performance Schema  for details. 

## 8.14 Examining Server Thread (Process) Information 

To ascertain what your MySQL server is doing, it can be helpful to examine the process list, which indicates the operations currently being performed by the set of threads executing within the server. For example: 

mysql> SHOW PROCESSLIST\G *************************** 1. row *************************** Id: 5 User: event_scheduler Host: localhost db: NULL Command: Daemon Time: 2756681 State: Waiting on empty queue Info: NULL *************************** 2. row *************************** Id: 20 User: me Host: localhost:52943 db: test Command: Query Time: 0 State: starting Info: SHOW PROCESSLIST 

Threads can be killed with the KILL  statement. See Section 13.7.8.4, “KILL Statement” . 

## 8.14.1 Accessing the Process List 

The following discussion enumerates the sources of process information, the privileges required to see process information, and describes the content of process list entries. 

## Sources of Process Information 

•Sources of Process Information 

•Privileges Required to Access the Process List 

•Content of Process List Entries 

Process information is available from these sources: 

•The SHOW PROCESSLIST  statement: Section 13.7.7.29, “SHOW PROCESSLIST Statement” 

