Hi Gerhard, I came across this myself a few weeks ago when I was wanting to increase the size of the DB vols I use from 2GB to 4GB. This DB was 100GB approx and so there were quite a lot of volumes to be deleted, and also on SSA. The elapsed time got longer as I did more volumes. It started at 20 minutes and was closer to an hour when the work was all finished - a week later (as I had to do just some of it each day). 2 hours seems excessive per vol.
Mirroring a volume on the other hand took just 3-4 minutes. I did look at iostat on all the disks when I was doing this and TSM server does seem to write to many volumes when it is doing deletes of a db-volume. Whether it is filling in little gaps or updating multiple tables I wouldn't know - you'd have to know full details of the internals (and we didn't cover this scenario at the Oxford Symposium when Dave Cannon presented on DB internals). I also observed that if you have multiple new and empty DB-vols that it wrote to all of them. It is something I would like to understand better. I did think of putting in a PMR to investigate but I needed to get on and not spend the time, possibly over several weeks getting the required diagnostics. In my expereience, this is the sort of TSM related performance problem that probably wouldn't be resolved very quickly ... Best wishes, Sheelagh -- Sheelagh Treweek Oxford University Computing Services Email: [EMAIL PROTECTED] Phone: +44 (0)1865 273205 Fax:-273275 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Importance: Normal Date: Thu, 12 Dec 2002 14:16:20 +0100 From: Gerhard Rentschler <[EMAIL PROTECTED]> Subject: Deleting dbvol takes long To: [EMAIL PROTECTED] I just deleted a 2GB DB volume. It took 2 hours to complete. The deleted volume resided on an SSA disk. The server CPU is not a bottleneck. Can anybody tell me why it is taking so much time? I first hoped it would do some DB reorg on the fly. But it obviously doesn't. Best regards Gerhard --- Gerhard Rentschler email:[EMAIL PROTECTED] Regional Computing Center tel. ++49/711/685 5806 University of Stuttgart fax: ++49/711/682357 Allmandring 30a D 70550 Stuttgart Germany
