标签：linux turn des shared bsp wap cleanup node code
1. 使用方法
/proc/sys/vm/drop_caches默认是0
# echo 1 > /proc/sys/vm/drop_caches; free pagecache, use
# echo 2 > /proc/sys/vm/drop_caches; free dentries and inodes
# echo 3 > /proc/sys/vm/drop_caches; free pagecache, dentries and inodes
注意：使用之前需要先sync，将缓存刷到磁盘中。
2. 实验
单位：MB # free -m total used free shared buff/cache available Mem: 1825 381 1363 8 79 1413 Swap: 0 0 0 # cp /etc/* /mytest/ # free -m total used free shared buff/cache available Mem: 1825 382 1341 8 101 1412 Swap: 0 0 0 过一段时间： # free -m total used free shared buff/cache available Mem: 1825 382 1341 8 101 1412 Swap: 0 # cat /proc/sys/vm/drop_caches 0 # sync # echo 3 > /proc/sys/vm/drop_caches # free -m total used free shared buff/cache available Mem: 1825 382 1405 8 37 1413 Swap:
3. 写个脚本做这个事情
# cat cleanup_cache.sh #!/bin/sh # drop_caches for every 5 mins drop_caches() { echo "Drop caches." sync echo 3 > /proc/sys/vm/drop_caches & return 0 } while true; do sleep 300 drop_caches done exit 0
4. 结论
Linux内核默认保持drop_cache的值是0，不建议经常修改它。
标签：linux turn des shared bsp wap cleanup node code
原文地址：https://www.cnblogs.com/hellokitty2/p/10088042.html
