Used Memory Not Clearing Down On Redhat Machines.

[Burke, Thomas G.]

Google linux memory useage, or some such.  This is normal behavior of the kernel - it allocates everything, almost as soon as it starts up.  It does this as an efficiency booster.  Better people than I are available to explain from a google search.

	-Tom 

-----Original Message-----
From: redhat-list-bounces at redhat.com [mailto:redhat-list-bounces at redhat.com] On Behalf Of Andrew.Bridgeman at corusgroup.com
Sent: Friday, August 12, 2005 10:27 AM
To: redhat-list at redhat.com
Subject: Used Memory Not Clearing Down On Redhat Machines.




We have 40 Redhat machines that run analysis jobs 24/7. We seem to have a problem with the memory usage once a job has finished and we are having to reboot the machines to clear the memory down every three weeks or so. The analysis jobs are stopped cleanly and are not leaving any rough processes at all so i do not understand why the machines are not freeing the memory up. The knock on affect of this is that jobs that are then run on these machines run dramatically slower as there is not enough memory to use. I have put the text from a top command below to help. Could someone please advise on what i can do to fix this issue.

15:20:33  up 14 days,  2:16,  1 user,  load average: 0.00, 0.00, 0.00
49 processes: 48 sleeping, 1 running, 0 zombie, 0 stopped CPU states:  cpu    user    nice  system    irq  softirq  iowait    idle
           total    0.8%    0.0%    0.2%   0.0%     0.6%    0.0%  198.4%
           cpu00    0.0%    0.0%    0.0%   0.0%     0.0%    0.0%  100.0%
           cpu01    0.8%    0.0%    0.2%   0.0%     0.6%    0.0%   98.4%
Mem:  3599032k av, 2926964k used,  672068k free,       0k shrd,   82052k buff
                    469844k actv, 1731916k in_d,   54940k in_c
Swap: 2044072k av,       0k used, 2044072k free                 2614264k cached

Regards

[IMAGE](Embedded image moved to file: pic31864.jpg)
**********************************************************************
This transmission is confidential and must not be used or disclosed by anyone other than the intended recipient. Neither Corus Group Plc nor any of its subsidiaries can accept any responsibility for any use or misuse of the transmission by anyone.
**********************************************************************