What version did you last see the problem? I'm interested as I'm about to put in a new TSM server, and I was contemplating which version to go to.
See Ya' Howard > -----Original Message----- > From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf > Of Matthew Glanville > Sent: Monday, April 07, 2008 8:44 AM > To: ADSM-L@VM.MARIST.EDU > Subject: Re: [ADSM-L] Improving TSM performance - memory related > setting > > Just a warning, don't necessarily go to 1/2 or 1/8th of your total > physical memory.. > > If your server has 64 GB of memory, 8 GB (1/8th) for BUFPOOLSIZE is > probably too high. I would keep it below 1 GB unless you prove to > yourself with some testing that it is helping speed up the backups or > restores. Just don't look at database cache hit rate. > > I think there's some inefficiency in how TSM database cache works, as > it > may have to search through that cached memory to find a hit. When you > are > caching 8 GB, that takes some time to search through all that. > > You'll see this as the dsmserv processes CPU use will increase the > larger > the BUFPOOLSIZE is. If it takes longer to search through that memory > than > it does to read the page from disk, you are hurting performance not > helping it by caching in memory. > > Maybe DB2 TSM in version 6 will help this issue. > I tried to put a problem in for it a few years back, but couldn't get > beyond level 2 since no one understood what I was talking about, they > kept > thinking the server was slow due to the operating system using it's own > page file to make up for the large memory setting, even though the 64 > bit > server had 32 GB of physical memory... Ahh well. I can use that other > 30 > GB for something else. > > or is it fixed now? > Matt G. > > > "ADSM: Dist Stor Manager" <ADSM-L@VM.MARIST.EDU> wrote on 04/04/2008 > 03:40:56 AM: > > > Bufpoolsize should be set between 1/2 and 1/8 of the among of the > > total physical memory, if I remember well, that is, what best > > practices recommend. > > Also if you modify this parameter you will have to take a look at > > the percentage hit cache (q db f=d) that can be increase (modifying > > the bufpolsize), or perhaps decrease if the setting is incorrect. > > Percentage hit cache must be above 99 %. > > > > I will also recommend to take a look at the performance tuning > > guide, that will let you know more about many settings that can > > increase the performance of your TSM server. > > > > Regards, > > Bernaldo. > > > > > > > > ----- Mensaje original ---- > > De: Paul Dudley <[EMAIL PROTECTED]> > > Para: ADSM-L@VM.MARIST.EDU > > Enviado: viernes, 4 de abril, 2008 5:44:02 > > Asunto: Re: [ADSM-L] Improving TSM performance - memory related > setting > > > > Currently the BUFPOOLSIZE is set to: > > > > BufPoolSize: 122,880 K > > > > The server has 3 Gb of memory. Is this something I can increase? > > > > Regards > > Paul Dudley > > > > Senior IT Systems Administrator > > ANL IT Operations Dept. > > ANL Container Line > > [EMAIL PROTECTED] > > 03-9257-0603 > > http://www.anl.com.au > > > > > > > > > -----Original Message----- > > > From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On > > > Behalf Of Skylar Thompson > > > Sent: Friday, 4 April 2008 1:05 PM > > > To: ADSM-L@VM.MARIST.EDU > > > Subject: Re: [ADSM-L] Improving TSM performance - memory related > > setting > > > > > > Paul Dudley wrote: > > > > If I recall correctly there is a TSM system setting that relates > to > > the > > > > memory available on the server, and you can check and adjust this > > > > setting to improve performance of your TSM server. > > > > > > > > > > > > > > > > Can anyone remind me which setting it is? > > > > > > > > > > > > > > Are you thinking of BUFPOOLSIZE and LOGPOOLSIZE? The former > controls > > > the > > > size of the database buffer pool (bounded only by the physical > memory > > of > > > the machine), and the latter the size of the temporary transaction > > space > > > in the recovery log (up to 8192 pages IIRC). > > > > > > -- > > > -- Skylar Thompson ([EMAIL PROTECTED]) > > > -- Genome Sciences Department, System Administrator > > > -- Foege Building S048, (206)-685-7354 > > > -- University of Washington School of Medicine