Cpulimit---控制cpu百分比

有一次，apche httpd进程cpu满100%了，后来发现下面的文章，然后转过来用了

安装CPU Usage Limiter for Linux

What is it?
cpulimit is a simple program that attempts to limit the cpu usage of a process (expressed in percentage, not in cpu time). This is useful to control batch jobs, when you don't want them to eat too much cpu. It does not act on the nice value or other scheduling priority stuff, but on the real cpu usage. Also, it is able to adapt itself to the overall system load, dynamically and quickly.
可以限制程序使用CPU的百分比,而不是时间.很好,很舒服.

开始安装吧.

官方地址:http://cpulimit.sourceforge.net/

cd /root/install/ 
svn checkout https://cpulimit.svn.sourceforge.net/svnroot/cpulimit/trunk cpulimit 

cd cpulimit 
make 

cp ./cpulimit /usr/sbin

限制方法:

如果限制进程名,比如将httpd这个进程名的CPU限制在40%

cpulimit --exe httpd --limit 40 
cpulimit --exe /usr/local/bin/httpd --limit 40

将pid为2960的进程的CPU限制在55%

cpulimit --pid 2960 --limit 55

慢慢对比top 命令那里的CPU变化.嘿嘿,有效果了吧?.

再来个完美的

自动限制当前进程使用CPU超过20%的进程,将他限制为10%

cpulimit --pid `ps aux|awk '{if($3 > 20) print $2}'` --limit 10

cpulimit命令:

Error: You must specify a target process, by name or by PID
Usage: cpulimit TARGET [OPTIONS...]
   TARGET must be exactly one of these:
      -p, --pid=N        pid of the process (implies -z)
      -e, --exe=FILE     name of the executable program file or absolute path name
   OPTIONS
      -l, --limit=N      percentage of cpu allowed from 0 to 100 (required)
      -v, --verbose      show control statistics
      -z, --lazy         exit if there is no suitable target process, or if it dies
      -h, --help         display this help and exit