Memory Usage Questions

[mnichols at atlantis.psi.siemens.com]

> How does one determine the system memory usage, both physical and virtual?
>
> "ps" and "top" both often report a programs size (SZ) as less than the
> resident size (RSS).  This does not seem reasonable.  Further, how does
> the space required for shared libraries get accounted ? Is it charged
> againt each program using the library ? Not accounted at all ?

I wondered the same thing and by sleuthing the man page for ps this is
what appears to be the answer question numero 2.

------------  excerpt from the ps(1) man page ---------------
     SIZE
     SZ      The combined size of the data and stack segments 
             (in kilobyte units)

     RSS     Real memory (resident set) size of  the  process 
             (in kilobyte units).

Note that SZ does not include the text segment this accounts for the
difference in the two values I would guess.

Mark Nichols			! internet: mnichols at psivax.psi.siemens.com
Pacesetter Systems Inc.		! voice: (818) 362-6822 x3104
Sylmar,  California 91342	!