"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU> wrote on 10/26/2005
12:02:44 PM:

> We are currently evaluating this product and have a few questions.  Our
> environment is:  TSM server 5.2.3.3 on AIX 5.2 and TSM backup client
> 5.3.0.8 and TSM TDP client 5.2.1.
>
> 1.  The restores are taking 2.5 times longer than the backups.  The
backup
> was created using stripes=6.  How do I speed this up?

It's hard to tell where your bottleneck is... but keep in mind that
restore can take longer because the SQL Server needs to preformat the
files
before it dumps data into them, regardless of the number of stripes.


> 2.  How do I get TDPSQL to perform a RESTORE Verifyonly on the backup
when
> it completes?

There is no "built in" RESTORE Verifyonly with Data Protection for SQL.
Many customers perform this by directing the restore to a different
database which gives a more complete "verification"
than a simple yes or no that verifyonly produces.


> 3,  Where is the backup compression rate listed when using TDPSQL?

It is not listed currently. You can calculate this my looking at the
size of the databases and then look at the TSM Server session statistics
for each stripe.

> 4.  Does the backup have to go directly to tape or can the diskpool be
> used?

No. It can go directly to disk, if you want. You need to make sure when
using striping that you use COLLOCATION by FILESPACE so that if the data
get migrated to tape, the striped data is kept on different tapes.
Otherwise, during a restore, there could be tape contention, reducing the
performance.


> 5.  Any other performance hints or tips?
>

You might also try playing with the TCP/IP settings in the DSM.OPT file
as well as the Data Protection for SQL "BUFFERS" and "BUFFERSIZE"
settings.


> Thank you.
>
>

Del Hoobler
IBM Corporation