MySQL参数优化辅助工具_mysqltuner.pl

简单说明（E文水平有限，有误之处，请多指教）

# ./mysqltuner.pl --help

  MySQLTuner 1.2.0 - MySQL High Performance Tuning Script

  Bug reports, feature requests, and downloads at http://mysqltuner.com/

  Maintained by Major Hayden ([email protected]) - Licensed under GPL

  Important Usage Guidelines:

     To run the script with the default options, run the script without arguments

     Allow MySQL server to run for at least 24-48 hours before trusting suggestions

#建议在MySQL服务器运行24-48小时，测试才有依赖性

     Some routines may require root level privileges (script will provide warnings)

#对于越权的权限会报警

     You must provide the remote server's total memory when connecting to other servers

#当连接其他服务器时，须提供远程服务器的总内存

  Connection and Authentication#连接、认证

     --host <hostname>    Connect to a remote host to perform tests (default: localhost)

--socket <socket>    Use a different socket for a local connection#通常在本机测试时使用

     --port <port>        Port to use for connection (default: 3306)

     --user <username>    Username to use for authentication

     --pass <password>    Password to use for authentication

  Performance and Reporting Options#性能报告选项

     --skipsize           Don't enumerate tables and their types/sizes (default: on)

#不列举表名以及类型和大小，默认打开，推荐打开此选项

                            (Recommended for servers with many tables)

-------- Storage Engine Statistics -------------------------------------------

[--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster

[--] Data in MyISAM tables: 392K (Tables: 116)

[--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 17)

[!!] InnoDB is enabled but isn't being used

[OK] Total fragmented tables: 0

     --checkversion       Check for updates to MySQLTuner (default: don't check)

#检查更新，加了该参数效果如下

#[OK] You have the latest version of MySQLTuner

#不加的话

#[--] Skipped version check for MySQLTuner script

     --forcemem <size>    Amount of RAM installed in megabytes

     --forceswap <size>   Amount of swap memory configured in megabytes

#设置物理内存和swap分区的大小（单位MB），这两个参数一般成对配置

#[--] Assuming 512 MB of physical memory

#[--] Assuming 1024 MB of swap space

  Output Options:

#输出显示的参数试一下就清楚了

     --nogood             Remove OK responses

     --nobad              Remove negative/suggestion responses

     --noinfo             Remove informational responses

     --nocolor            Don't print output in color

例如

./mysqltuner.pl --socket /var/lib/mysql2/mysql2.sock

……

-------- Performance Metrics -------------------------------------------------

[--] Up for: 23h 37m 18s (542 q [0.006 qps], 176 conn, TX: 442K, RX: 33K)

下面是该程序给的一些修改建议，大家可参考修改。有时间的话，还可以用sysbench进行测试。

-------- Recommendations -----------------------------------------------------

General recommendations:

   Add skip-innodb to MySQL configuration to disable InnoDB

   MySQL started within last 24 hours - recommendations may be inaccurate

   Reduce your overall MySQL memory footprint for system stability

   Enable the slow query log to troubleshoot bad queries

   Set thread_cache_size to 4 as a starting value

Variables to adjust:

 *** MySQL's maximum memory usage is dangerously high ***

 *** Add RAM before increasing MySQL buffer variables ***

   query_cache_size (>= 8M)

   thread_cache_size (start at 4)