脚本作用：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。

脚本如下 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。