I can not commit to providing answers to this, but I have forwarded the
questions to some of our performance engineers as well as server
developers. I do not even know if any analysis in this area has been done
for TSM. These are good questions, but I suspect that, as in all aspects
of system management, there is no single "right" answer.

Regards,

Andy

Andy Raibeck
IBM Software Group
Tivoli Storage Manager Client Development
Internal Notes e-mail: Andrew Raibeck/Tucson/IBM@IBMUS
Internet e-mail: storman AT us.eyebm DOT com (change eye to i to reply)

The only dumb question is the one that goes unasked.
The command line is your friend.
"Good enough" is the enemy of excellence.




Steve Schaub <Steve.Schaub AT HAWORTH DOT COM>
Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
05/23/2003 07:08
Please respond to "ADSM: Dist Stor Manager"


        To:     ADSM-L AT VM.MARIST DOT EDU
        cc:
        Subject:        Re: anyone using ATA disk systems



Hey Andy R, how about getting some Tivoli developers on the server-side
to throw some answers at this.  I have spoken with many users, business
partners, & architects and have yet to get a consistant picture.  Some
insist that using one huge diskpool works fine, others say the disk
format leads to disastrous fragmentation and the only way to go is file
class volumes, still others say not to even try this approach.  Maybe a
Tivoli white paper specifically addressing disk-only primary storage
pools would give a definitive answer?

-----Original Message-----
From: Talafous, John G. [mailto:Talafous AT TIMKEN DOT COM]
Sent: Friday, May 23, 2003 9:26 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: anyone using ATA disk systems


We too are considering a mass expansion of our storage pools to
implement Disk to Disk backup via TSM. The reason is to enhance recovery
times. The Nexsan ATABeast is under consideration.  We currently have
about 40TB backed up to TSM storage pools. I am thinking of bringing in
MANY TB of ATABeast so that we can discontinue migration to tape. I am
curious as to what happens internally in TSM when you drive your storage
pool utilization to, say, 80% and hold it there?  Are there any
performance penalties?  Any cautions? Any real world experience?  How
much ATA should I consider?

TIA,
John G. Talafous              IS Technical Principal
The Timken Company            Global Software Support
P.O. Box 6927                 Data Management
1835 Dueber Ave. S.W.         Phone: (330)-471-3390
Canton, Ohio USA  44706-0927  Fax  : (330)-471-4034
talafous AT timken DOT com           http://www.timken.com


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