shell脚本检测tomcat进程占用内存大小

脚本做用：监控运行中的tomcat内存占用大小，当内存超过所定义的最大使用内存时，自动重启tomcat，达到释放内存的效果。

脚本以下 check_tomcat.sh：

#!/bin/bash
#by Lia
#check tomcat process memery.
#

#define tomcat process, if outride the number, then restart tomcat server.

#4194305 kb = 4 G
tomcat_mem=4194304

#get pids of tomcat5,tomcat6
tomcat_pid=`ps -ef | grep tomcat | grep java | awk 'NR==1 {print $2}'`
echo $tomcat_pid

#get tomcat5's memery(KB).
tomcat_mem=`cat /proc/$tomcat_pid/status | grep -e VmRSS | awk 'NR==1 {print $2}'`
echo $tomcat_mem

#tomcat env
tomcat_home=/opt/tomcat

#define tomcat restart function
function restart_tomcat()
{
pid=`ps aux | grep tomcat | grep -v grep | grep -v retomcat | awk '{print $2}'`
echo $pid

cd $tomcat_home/bin

if [ -n "$pid" ]
then
{
echo ===========shutdown================
./shutdown.sh
sleep 10

pid=`ps aux | grep tomcat | grep -v grep | grep -v retomcat | awk '{print $2}'`
if [ -n "$pid" ]
then
{
sleep 2
echo ========kill tomcat6==============
kill -9 $pid
}
fi
sleep 3
echo ===========startup.sh==============
./startup.sh
}
else
echo ===========startup.sh==============
./startup.sh
fi
}

#check log dir or not, then mkdir log dir
[ ! -d logs ] && mkdir -pv logs

#if tomcat process memery outride tomcat_mem, then restart tomcat server.
if [[ $tomcat_mem -gt $tomcat_mem ]]; then
echo `date "+%F %T"` [Tomcat5 RUNNING]Tomcat\'s memery is outride.>>logs/restart_tomcat_`date "+%F"`.log
restart_tomcat
else
echo `date "+%F %T"` [Tomcat5 RESTART]Tomcat\'s memery not outride.>>logs/restart_tomcat_`date "+%F"`.log
fi

可将脚本写入crontab中，定时检测。