Need to release Cache memory

Linux and Unix-Like Red Hat
1

Right now i am using Red Hat Enterprise Linux AS release 4 and cache memory occupying around 1.5GB mentioned below,

            total       used       free     shared    buffers     cached 
Mem:   2026       2021          5          0        161       1477 
-/+ buffers/cache: 382       1644 
Swap:  4094          0       4094

I have tried

sync; echo 3 > /proc/sys/vm/drop_caches

but it was not working in EL4 and its seems to be working in fedora...

I need solution to release the cache memory, Please anyone suggest me to sort out the issue...

2

whats your kernal version ?

this cache clear method is introduced in 2.6.16

try this..

 
sudo sync && sudo bash -c 'echo 3 > /proc/sys/vm/drop_caches';
3

I'm having the Kernel version is Linux "my.com-Test 2.6.9-55.ELsmp"
--> Let me know if any otherway is there to release the cache?

4

How do you know it's not working? Any error messages?

Also I wonder why would you like to clear the memory cache?

5

You are having the standard linux newbie memory freakout. It's not "occupying" 1.5G, since cache counts as free memory and doesn't need to be "released" -- your system will recycle and reuse cache as ordinary memory at need. But until it's needed, you want idle memory to be used as cache because it makes your system faster. Memory that sits around doing nothing is wasted.

You might want to undo whatever changes you did to /proc/sys/vm. If you managed to do anything at all it's probably hurting your system performance.