clean up memory on linux

sync; echo 3 | sudo tee /proc/sys/vm/drop_caches
where proc filesystem mounted under /proc
Sample Output
3

9
By: bandie91
2010-05-23 11:39:35

7 Alternatives + Submit Alt

What Others Think

Why would you want to do this?
DNSpyder · 421 weeks and 6 days ago
Nice, but what would you use it for other than prettying up /usr/bin/free for management's consumption?
sufoo · 421 weeks and 6 days ago
Buffers and caches in linux only use unused memory, i.e. memory not used by processes. So it's incorrect to think that you are making more memory available for programs by using this, in general. As soon as an application makes a big memory request, the kernel may satisfy that request by "dropping" enough buffers or cache to satisfy the request. Because unused memory is a terrible thing to waste. :-) If you do this, and then want to cache a file's contents (if there is memory available) then simply do cat filename > /dev/null if you run htop you can see the cache fill up as cat reads this file and automatically uses cache if it can.
bwoodacre · 421 weeks and 6 days ago
bwoodacre: its news for me. i had hope it decrease number of pagefaults
bandie91 · 421 weeks and 4 days ago
under what situation i should use this command??
criver · 419 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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