• "System Monitor" tells me i am using 1.3GB of 2.9GB at 42.8% "atop"
  • tells me i am have 174.8M Free "top"
  • tells me i have 3072772 total, 2894424 used, 178348 free

3072772KB = 2.93042373657227GB "top" total

3040870.4KB = 2.9GB "System Monitor" total

**2894424**KB = 2.76033782958984GB "top" used

**1363148.8**KB = 1.3BG "System Monitor" used

174.8M = 0.170703125GB "atop" free

0178348KB = 0.170085906982422GB "top" Free

1531275.2 KB or 1.46GB diffrence between Top Used and System Monitor used

That is a lot of RAM not accounted for if i only have 0.17GB of RAM Free

Is there a problem with one of the programs I should know about? Is the "root" user using 1.5 GB of ram?


System Monitor doesn't count memory currently assigned to the cache as used, top does. free lists both figures. System Monitor is generally more correct since Linux tries to use almost all free memory to cache disk files in the hopes it will do some good, and unused free memory is a waste. It is freed immediately as needed, so for most purposes, can be considered free.


This is just a misunderstanding of terms. Both you and Linux agree that memory taken by applications is "used", while memory that isn't used for anything is "free".

But what do you call memory that is both used for something and available for applications?

You would call that "free", but Linux calls it "used".


from: www.linuxatemyram.com

System Monitor tells the used memory as you would call it, but atop/top tell as Linux calls it.

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