kswapd process
Hi All, We have Informix 11.10.FC2 on SLES 10 SP1 kernel version 2.6.16.46-0.12-smp. We have 46GB on the server of which 42GB is devoted to informix. Whenever we are trying to increasing the buffers from 14GB to 30GB, the "kswapd" process utilizes maximum CPU hampering the server performance. The kswapd process is also not doing any swapping. what is the issue or relation with the "kswapd" process when we increase the buffers? Regards, Sushant
Do you have RESIDENT set to something other than zero(0)? One idea: Linux will try to use any memory not used by other processes (up to about 25% so 11.5GB) for system buffer cache. It may be that increasing the Informix memory is causing the buffer cache to be swapped out or at least to be reorganized. Art Art S. Kagel Advanced DataTools (www.advancedatatools.com) Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Wed, Apr 18, 2012 at 9:02 AM, SUSHANT KODE <ksushants@gmail.com> wrote: > Hi All, > > We have Informix 11.10.FC2 on SLES 10 SP1 kernel version > 2.6.16.46-0.12-smp. > > We have 46GB on the server of which 42GB is devoted to informix. Whenever > we > are trying to increasing the buffers from 14GB to 30GB, the "kswapd" > process > utilizes maximum CPU hampering the server performance. The kswapd process > is > also not doing any swapping. > > what is the issue or relation with the "kswapd" process when we increase > the > buffers? > > Regards, > Sushant > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --14dae93403c398d26004bdf3bc8b
Kswapd job is too look/maintain free pages so by increasing IDS to 30GB my bet is you have passed the threshold and kswapd is becoming more aggressive. Do you have swap configured, if so how much ? Have you tuned swappiness and vfs_cache_pressure? Cheers Pauk -----Original Message----- From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of SUSHANT KODE Sent: Wednesday, April 18, 2012 8:02 AM To: ids@iiug.org Subject: kswapd process [26733] Hi All, We have Informix 11.10.FC2 on SLES 10 SP1 kernel version 2.6.16.46-0.12-smp. We have 46GB on the server of which 42GB is devoted to informix. Whenever we are trying to increasing the buffers from 14GB to 30GB, the "kswapd" process utilizes maximum CPU hampering the server performance. The kswapd process is also not doing any swapping. what is the issue or relation with the "kswapd" process when we increase the buffers? Regards, Sushant **************************************************************************** *** Forum Note: Use "Reply" to post a response in the discussion forum.