drop the page cache,inode and dentry caches , which can free up a huge memory. Now you can free the  allocated  ton of memory just to get rid of the cache

Note : run ‘sync’ before dropping the caches, so that all the dirty pages could be acted upon
To free memory, steps follows:

1. frees only page cache run below command

admin@smartproteam-linux$ echo 1 > /proc/sys/vm/drop_caches

2.freeing dentry caches and inodes run below command

admin@samrtproteam-linux$ echo 2 > /proc/sys/vm/drop_caches

3.freeing all of the page cache,inode and dentry run below command

admin@samrtproteam-linux$ echo 3 > /proc/sys/vm/drop_caches