Real vs Reported SPLAT Free Memory Usage

OK, so you can ignore ‘top’ command. Boned.
I’m doing some sizing on our MDS boxes and came across this. I was using the GAIA memory usage tool and it reported different stats than top.
You have to use ‘free’ command and add up “free + buffers + cached” and then you get the right free memory

Example:

# free -k -t

total             used              free         shared    buffers     cached

Mem:                               1295840      1272788      23052          0      51200     996336
-/+ buffers/cache:     225252       1070588
Swap:                                1028120     179912        848208
Total:                                2323960    1452700     871260
In the example above, the system is mostly idling, with only OS processes running (‘cpstop‘ed the kernel). The OS reports “1272788” of “1295840” used.  However, we see that the ‘free’ + ‘buffers’ + ‘cached’ = “23052” + “51200” + “996336” = “1070588”, which is ‘logically’ free for applications to use, and will be handed out by the kernel appropriately. So in reality there is more than 23052 of free memory, there is 1070588 of free memory.

 

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blog.lachmann.org

Michael Endrizzi's - St. Paul MN - CheckPoint blog on topics related to Check Point products and security in general.

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