Hi, I have noticed that it is very bad for performance to have 10+ diskpools (we had close to 50 volumes) on one raid5 volume, and have multimpe volumes being accessed at the same time. We greatly increased throughput by breaking our raid5 down into jbod, having just a few diskpool volumes on a disk, and never more than one per storagepool. My disks now do 10+ MB/s (even as much as 20 MB/s) each, while the raid5 did about the same for the whole raid5 volume. Even worse the raid5 would start to trash during busy hours because TSM concurrently accesed so many different files on this one raid5. Which is not an issue any more.
On woensdag, juli 24, 2002, at 06:00 , Steve Freeman wrote: > Please could someone advise me on the following issue we have with tsm. > I am a TSM novice and would appreciate some pointers etc. > > Environment : TSM 4.2.0 AIX4.3.3 ML09 Server and Client on same Server > using Sharedmem > > 2 Stgpools defined diskpool and tapepool > > we have created a diskpool on RAID5 and created random access volumes > Total Diskpool size is 150GB. Our nextpool is tapepool for migration > upon high thresholds being reached. > > We have compression turned off on the client and set the selftune > parameters in dsmserv.sys > SELFTUNEBUF > SELFTUNETXN > > > Issue: IF we initiate a client backup using sharedmem to the diskpool, > it seems to take the same time as it does to backup the client straight > to tapepool. I would have thought the diskpool access > would be quicker ? > > The Diskpool is located on direct fibre attached storage with large > read/write cache. The tapepool > is SCSI attached ATL library with 2 drives > > Any suggestions or pointers to increase the throughput to a respectable > level would be appreciated. > > kind regards > steve freeman > [EMAIL PROTECTED] > > --- Met vriendelijke groeten, Remco Post SARA - Stichting Academisch Rekencentrum Amsterdam http://www.sara.nl High Performance Computing Tel. +31 20 592 8008 Fax. +31 20 668 3167 "I really didn't foresee the Internet. But then, neither did the computer industry. Not that that tells us very much of course - the computer industry didn't even foresee that the century was going to end." -- Douglas Adams
