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Mysql压力测试shell脚本
Mysql自带了压力测试工具mysqlslap,所以我们可以不用自己编写程序来测试Mysql读取的压力。压力测试shell脚本如下: www.bitsCN.com
[plain]
#!/bin/sh
while true
do
mysqlslap --concurrency=100 --iterations=10 --create-schema='test' --query="insert into test(c1,c2,c3,c4) values(1,1,1,'a')" --number-of-queries=200 --debug-info -uroot -p123456
usleep 100
done
上面脚本的意思是每隔100ms循环做这样的事:模拟100个mysql客户端,对数据库test的表test执行200次插入(number-of-queries = concurrency * 每个mysql客户端的查询次数,所以这里的每个mysql客户端的查询次数是2次),迭代10次。--debug-info是打印内存和CPU的相关信息。
接着我们可以编写shell脚本来输出指定时间间隔(比如1秒)内的mysql操作次数,shell脚本如下:
[plain]
#!/bin/sh
lastTimes="0"
while true
do
currentTimes=$(mysql -uroot -p'123456' -e "show global status like 'Com_insert'" | sed '1d' | awk '{print $2}')
times=$(expr ${currentTimes} - ${lastTimes})
lastTimes="${currentTimes}"
echo "${times}"
sleep 1
done
查看mysql各种操作的次数,可以通过查看global status里的'Com_'开头的变量,它们就是mysql的操作命令,比如Com_insert就是插入命令、Com_update就是更新命令,等等,具体可以查看文档说明。将相邻两次的次数相减,就得到这个时间间隔内执行的次数。
PS:除了iostat等命令外,也可以通过top命令来查看io的负载(看wait的百分比,如果大于等于 1 / cpu核数,则说明硬盘IO有问题)。请参考英文文章:Understanding Disk I/O - when should you be worried?
来源 http://blog.csdn.net/skyman_2001
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