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Please, I need a help. I have a Linux that has the following scenario of RAM memory consumption:

root@cpro15623 [~]# free -m
             total       used       free     shared    buffers     cached
Mem:          3881       3216        665          0         98       1555
-/+ buffers/cache:       1562       2318
Swap:          991          0        991

But Swap is not being used and my server is too low!

This is vmstat results:

root@cpro15623 [~]# vmstat
procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu-----
r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
302 35      0 1022128 100784 1596548    0    0    23   282  750  877 28 58 14  0  1

Thanks everybody!

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marked as duplicate by Michael Hampton, EEAA, Tom O'Connor, Ward, mgorven Feb 26 '13 at 4:41

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Add output of top would help. Is your php doing any database queries? – ETL Feb 25 '13 at 23:54
Trust the OS to manage system memory better than you think you can. – Tom O'Connor Feb 26 '13 at 0:31

This is normal. The Linux kernel will use free memory to buffer disk access, thereby speeding up your system overall.

Help! Linux ate my RAM!

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But my system is too slow at this moment! A lot of php processes under execution. Sometimes my server responds, other times not... What could it be? – Marcelo Juventino Feb 25 '13 at 23:45
@MarceloJuventino - well, that's an entirely different question. This question is probably going to be closed as a dupe of the other same memory question - feel free to ask another question about your actual problem. – Mark Henderson Feb 25 '13 at 23:59

Read this way:

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(stuff to overcome stupid 30 chars least limit)

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