In my experience with TSM on AIX, and by reading some other docs, I
think I can confidently state the following...

TSM's database is a relational database - it relates information
organized into tables with one or many others.
TSM supports a subset of SQL to allow you access to the tables in
TSM's internal database.
TSM's similarities with DB2 ends at the point of being relational and
supporting SQL.

As for sizing my systems...  I don't think I have a TSM database in
excess of 2GB at my customer locations, however, all standard
disk-performance logic applies...

Databases and logs need their own physical disks, and preferably have
separate controllers.
Use RAID to get performance benefits from striping data across
multiple physical disks and getting faster total throughput.
In RAID,sometimes more disks of smaller capacity are better than
fewer disks of larger capacity.
Upgrading to faster disks (10k RPM) or increasing your disk
subsystems RAM cache help too.

-JD.

We have several TSM 4.2 servers running on both z/OS and AIX and have
We have several TSM 4.2 servers running on both z/OS and AIX and have
concerns about the TSM DB size as it impacts our ability to run maintenance
operations like DB Audits, Reorgs, and SQL Queries also seem to take much
longer than they should on some systems.

I am curious what DB Sizes others have found manageable. The only answer we
have been able to get from our Tivoli contacts is that we should not exceed
50GB. This seems much too large given that a DB Rerog on a 50GB database
requires us to schedule a 36 hour outage (unload, format, reload process on
z/OS).

1) How do other TSM shops size their TSM DB's?

I have heard both that the TSM DB is based on DB2, and that is in no way
related to DB2 from various Tivoli support people. I have seen some
discussion here and on ADSM.org about DB tuning practices with the
assumption that this is a variation of DB2. One of our admins recently
attended a TSM 4.1 class and in his textbook there is a comment "All though
the TSM database is not a relational database....an interface makes it
appear as one".
(TSM 4.1 Enhancements, Tuning, and Troubleshooting, section 10-3)

2) Does anyone here know definitively if the TSM DB is or isn't a DB2
variant?

Thank You,

Al Bratlie
Lead Systems Engineer
Enterprise Storage Group
Thomson Legal and Regulatory Group Technical Services
"All views and opinions expressed are those of the author and have not been
approved or reviewed by TLRTS"