/dev/shm (shared memory) on linux

Posted by Kirzilla on Server Fault See other posts from Server Fault or by Kirzilla
Published on 2010-04-21T11:08:04Z Indexed on 2010/04/21 11:14 UTC
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linux

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unix

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memory-usage

Hello,

Let's imagine that we have 8Gb of RAM on server. I'm mounting /dev/shm with 4Gb on board.

mount -o remount,size=4G /dev/shm

Will this memory be strictly reserved for shared memory or if /dev/shm is empty this memory could be used by regular applications (web server, php etc.)?

PS:Sorry for my English.

I'm asking it because I've just checked df -h and found tmpfs 6.0G 0 6.0G 0% /dev/shm on 8Gb RAM sever. I don't know who made this setup, but it seems to me awful.

Thank you!

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