Drop
sync
echo 1 > /proc/sys/vm/drop_caches
drop_caches
Writing to this 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.