[hobbit] linux memory usage

[Dominique Frise]

Taylor Lewick wrote:
> When I pull up hobbit graphs for memory for one of our database servers with 16 GB of memory, I see the Actual Memory Used is reporting as 657 M and swap is 0 M Used.
> 
> But if I run ps -vax --sort -rss  note the top 4 processes...
> Looks like just over 7.0 GB of memory is consumed.
> 
> I'm deleting PID, TTY and STAT colum to make sure it all fits on one line.
> 
> TIME  MAJFL   TRS   DRS   RSS %MEM COMMAND
> 12:39      4  3519 3310360 3193428 19.4 postgres: 
>  4:22      0  3519 3312708 3077228 18.7 postgres: 
>  0:31      0  3519 3312832 993816  6.0 postgres: 
>  0:26      0  3519 3312128 192740  1.1 postgres: 
> 
> Output of free shows...
> 		total       used       free     shared    buffers     cached
> Mem:      16433348   16252424     180924         0     168500   15409800
> -/+ buffers/cache:     674124   15759224
> Swap:      8355832        540    8355292
> 
> So is the system telling me that most of the memory the processes are taking up from the ps -vax output is cached and can be released at any time?
> 

That is also what I understand.
"Actual" shows memory that cannot be released.
This value is the one to watch.

Dominique