分类: 电脑技术
作者: admin
自动释放linux内存
 

手动去释放内存命令:

free -m
sync
echo 1 > /proc/sys/vm/drop_caches
echo 2 > /proc/sys/vm/drop_caches
echo 3 > /proc/sys/vm/drop_caches free -m

手动写入自动清理并做记录的sh命令脚本:

1)在root目录下创建一个freemem.sh的脚本:

# vi freemem.sh

复制如下脚本进去:

#!/bin/bash  

used=`free -m | awk 'NR==2' | awk '{print $3}'`
free=`free -m | awk 'NR==2' | awk '{print $4}'`
echo "===========================" >> /var/log/mem.log
date >> /var/log/mem.log
echo "Memory usage | [Use:${used}MB][Free:${free}MB]" >> /var/log/mem.log
if [ $free -le 100 ] ; then
 sync && echo 1 > /proc/sys/vm/drop_caches
 sync && echo 2 > /proc/sys/vm/drop_caches
 sync && echo 3 > /proc/sys/vm/drop_caches
 echo "OK" >> /var/log/mem.log
else
 echo "Not required" >> /var/log/mem.log
fi
exit

按esc输入:wq,保存退出!
2)加入Linux Crontab 定时任务:

# echo "00 00 * * * root /root/freemem.sh" >> /etc/crondtab

经过测试,发现完全可行

#! /bin/bash   
# cache释放:   
# To free pagecache:   
sync 
sync 
#echo 1 > /proc/sys/vm/drop_caches   
# To free dentries and inodes:   
#echo 2 > /proc/sys/vm/drop_caches   
# To free pagecache, dentries and inodes:   
echo 3 > /proc/sys/vm/drop_caches