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Functions

free up memory

Terminal - free up memory
echo 3 > /proc/sys/vm/drop_caches
2012-08-05 19:35:14
User: andreisid
Functions: echo
-4
free up memory

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
sync; echo 3 | sudo tee /proc/sys/vm/drop_caches
2010-05-23 11:39:35
User: bandie91
Functions: echo sudo sync tee
9

where proc filesystem mounted under /proc

sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
/sbin/sysctl -w vm.drop_caches=3
2012-08-05 22:09:04
User: jlaunay
4

=1 --> to free pagecache

=2 --> to free dentries and inodes

=3 --> to free pagecache, dentries and inodes

sync; echo 3 > /proc/sys/vm/drop_caches
sysctl -w vm.drop_caches=3

Know a better way?

If you can do better, submit your command here.

What others think

Better use sysctl instead of echo :

/sbin/sysctl vm.drop_caches=3o

1 --> to free pagecache

2 --> to free dentries and inodes

3 --> to free pagecache, dentries and inodes

Comment by jlaunay 102 weeks and 3 days ago

Why would calling sysctl be better than calling echo?

Comment by wr8cr8 102 weeks and 2 days ago

There is no big difference but with echo you can make a mistake, for example echo 4 or any bad value will work but sysctl is a tool especially designed to configure kernel parameters:

/sbin/sysctl -w vm.drop_caches=4

sysctl: setting key "vm.drop_caches": Argument invalide

vm.drop_caches = 4

Sysctl also allow you to edit /etc/sysctl.conf to make the change permanent.

Comment by jlaunay 102 weeks and 2 days ago

Your point of view

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