How to Clear Memory cache in Linux !!!

Clearing the Linux Memory cache can be a quick way to regain system resources. Writing to the drop_cache process will cause the kernel to drop clean caches, dentries and inodes from memory, causing that memory to become free.

To free pagecache:# 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

As this is a non-destructive operation, and dirty objects are not freeable, the user should run “sync” first in order to make sure all cached objects are freed.

Example – Memory before:

[root@server ~]# free -m
total       used       free     shared    buffers     cached
Mem:          7860       7040        820          0        343       5076
-/+ buffers/cache:       1620       6240
Swap:         3999          0       3999

[root@server ~]# sync
[root@server ~]# echo 3 > /proc/sys/vm/drop_caches

Memory after:

[root@server ~]# free -m
total       used       free     shared    buffers     cached
Mem:          7860       1279       6581          0          0         33
-/+ buffers/cache:       1245       6615
Swap:         3999          0       3999

 

Vishwajit Kale

Vishwajit Kale blazed onto the digital marketing scene back in 2015 and is the digital marketing strategist of Hostripples, a company that aims to provide affordable web hosting solutions. Vishwajit is experienced in digital and content marketing along with SEO. He's fond of writing technology blogs, traveling and reading.

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