Clear the cache memory in Linux

By default the Linux OS has a very efficient memory management process that should be freeing any cached memory on the machine that it is being run on. However when it comes to Cached memory the Linux OS may at times decide that the Cached memory is being used and is needed which can lead to memory related issues and ultimately rob your server of any potentially free memory. To combat this you can force the Linux OS to free up and stored Cached memory.

In Linux, you can clear the cache of the memory by using

sync; echo 3 > /proc/sys/vm/drop_caches

You can write shall script for the same..

Type crontab -e as this will allow you to edit cron jobs for the root user.


Scroll to the bottom of the cron file using the arrows key and enter the following line:
0 * * * * /root/clearcache.sh
Create a file in '/root' called 'clearcache.sh' with the following content:

#!/bin/sh
sync; echo 3 > /proc/sys/vm/drop_caches
Once you have saved this file, the job is complete!

Every hour the cron job will run this command and clear any memory cache that has built up.

:)