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clear the cache from memory

Terminal - clear the cache from memory
sync; echo 3 > /proc/sys/vm/drop_caches
2009-08-20 17:28:56
User: lunarblu
Functions: echo sync
clear the cache from memory


There are 3 alternatives - vote for the best!

Terminal - Alternatives
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
sysctl -w vm.drop_caches=3
sudo sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches
2012-03-17 08:27:58
User: StephenJudge
Functions: echo sudo sync tee
Tags: memory cache

"That's it. Not much to see here. The first command writes any cache data that hasn't been written to the disk out to the disk. The second command tells the kernel to drop what's cached. Not much to it. This invalidates the write cache as well as the read cache, which is why we have the sync command first. Supposedly, it is possible to have some cached write data never make it to disk, so use it with caution, and NEVER do it on a production server. You could ... but why take the risk?

As long as you are running a post 2.6.16 kernel,..."

Source: http://ubuntuforums.org/showpost.php?p=3621283&postcount=1

echo 3 > /proc/sys/vm/drop_caches

Know a better way?

If you can do better, submit your command here.

What others think

Won't the kernel automatically sync dirty pages to disk when you drop caches? It seems like the sync is redundant.

Comment by bwoodacre 320 weeks and 4 days ago

Your point of view

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