try vmstat, see all the options in "man vmstat" it reads from /proc/meminfo and /proc/stat #vmstat -a 5 -S m on my system with 2 GB ram it shows that i'm having 18 mb free, 922 mb inactive and 821 mb active my running processes only use a tiny bit of my active ram, you can check it with: #ps aux | awk '{print $4"\t"$11}' | sort | uniq -c | awk '{print $2" "$1" "$3}' | sort -nr This is normal behavior, for better understanding please read this excellent article from redhat: http://www.redhat.com/magazine/001nov04/features/vm/ Sander John Doe wrote: > From: Peter Kjellstrom <cap at nsc.liu.se> > >> On Monday 06 July 2009, John Doe wrote: >> >>> When I do a free, I get: >>> total used free shared buffers cached >>> Mem: 18482800 18030668 452132 0 683068 9426792 >>> -/+ buffers/cache: 7920808 10561992 >>> But, when I do a ps, mysql is the only process that takes noticable memory; >>> and it is far from 7.9GBs... >>> USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND >>> mysql 28346 36.0 15.6 3241196 2884692 ? Sl Jul04 981:19 \_ >>> Once you removed the buffers and the cached memory from the total used >>> memory... what is left? Looks like I have "something" (that is not >>> buffers/cached) that takes more than 4GB... Could it be disk cache or is it >>> included in the cached value? >>> >> /proc/meminfo may give you a more detailed summary. >> > > Sadly, not much more information in /proc/meminfo... > Same values as in free, since free reads it. > Basicaly, 7.9GB are apparently used, but the sum of the memory used by all the processes is around 3.5GB... > > JD > > > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >