The recovery log size requirements can be significantly greater in Version 2
of ADSM as opposed to Version 1.  In version 1,  the recovery log size is
dependent upon the amount of concurrent activity taking place.  We're
running ADSM version 1 with a 5 GB database... our recovery log is sized at
500 MB which is much bigger than it needs to be but I sized it with going to
Version 2 in the near future in mind.  Would also recommend keeping the
recovery log on separate physical volumes than the database.  If you're
running version 1 of ADSM, I'd start with a 50-75 MB recovery log and keep
an eye on it.  The 'Q LOG FORMAT=DETAILED' command will tell you what the
maximum utilization since the last time ADSM was started.

Tim Pittson
pittson1 AT bwmail1.hcc DOT com
 ----------
From: owner-adsm-l
To: Multiple recipients of list ADSM-L
Subject: DASD configuration questions
Date: Friday, October 20, 1995 11:28AM

What size should your recovery log be? I know the manual says to start
out at 12Mb and then increase it as needed. Well I would like to get
the recovery log as close to the correct size as possible when I start.
We are running the server under VM ESA, on a 9221-200. We are going to
start out with about 100 users and expand from there. We are looking at
500-1000 users before we have to start adding resources. There is a
possibility of 7000+ users if ADSM goes over well. It would take about
one to two years to get to 7000+ users. We also realize that we will
need to add additional resources for this to happen.

At this time I have 8900 cylinders of DASD that I can split up between
the database, storage pool, and recovery log. We are not going to mirror
at this time due to resource restrictions. The 8900 cylinders are on
four HDA's with 2225 cylinders each.

I was planning on having 1200 cylinders/HDA for the database, 1000
cylinders/HDA for the storage pools and 25 cylinders/HDA for the
recovery log. Does this look like a good configuration? Is the recovery
log going to be too small? I have maxusers set to 25 at this time.

Any comments or suggestions would be greatly appreciated.