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- Why drop caches in Linux? 10 answers
Additionally I do have language files that are written to flat files on the server where cached ram definitely is good rather than reading from disk. But there are only a handful of files like this.
In about a two weeks I've gone from having 98% free ram to 4% free ram. This has occurred during a time in which we also push several large svn updates onto the server.
My question is whether my server will be better tuned if I periodically clear my cache (I'm aware of Linus Torvalds' feeling about cache) using the following command:
sync; echo 3 > /proc/sys/vm/drop_caches
Or would I be better off editing the following file:
If I replace the default value of 60 with 30 I should have much less swapping going on and a lot more reuse of stale cache.
It sure feels good to see all that cache freed up using the first command but I'd be lying to you if I told you this was good for the desktop environment. But what about a web server like I've described above? Thoughts?
EDIT: I'm aware that the system will acquire memory as it needs it from the cache memory but thanks for pointing that our for clarity. Am I imagining things when Apache slows down when most of the server memory is stored in cache? Is that a different issue altogether?