ADSM-L

performance of restore v. retrieve v. backupset restore

2005-10-13 11:57:51
Subject: performance of restore v. retrieve v. backupset restore
From: Nancy Reeves <Nancy.Reeves AT WICHITA DOT EDU>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Thu, 13 Oct 2005 10:57:30 -0500
We are moving off of one disk array onto another, and I have 3 windows
machines that have filesystems that need to be moved. We have come to the
conclusion that using TSM to move the data will be the simplest and most
straight forward way to do it. I am trying to decide whether to do a plain
restore, create a backupset and restore it, or use archive. I am reading
the ADSM Quick Facts file to learn about performance issues.

The clients are all 5.2.2.0 The server is also 5.2.2.0 on AIX. We have
LTO2 tapes in a robot with 6 drives. Each disk volume to be moved is 39.9
G. One is 20% full, one is 50% full, and one is 95% full.

Since  my tapes hold 200G, if I use a backupset, I will have only 1 tape
mount.
However, if I use a regular restore, I can have the restore multiple
threads and drives (given that maxnummp is high and mountretention is
low).
I do not have collocation on, but I could change that and "force" a full
backup of the filesystems that need to be moved, so they would be
collocated, but that wouldn't be much different than using a backupset,
would it?

Any advice?

Nancy Reeves
Technical Support, Wichita State University
Nancy.Reeves AT wichita DOT edu          316-978-3860