Charles,

I may be missing something here, but even your numbers out of the
Symetrix seem pretty bad.  Are you sure you didn't drop a "0"
somewhere?  I have one customer that I set up using SSA drives with JFS2
filesystems and LTO1 drives and we average between 35 and 40MB/sec. and
some days as high as 45MB/sec (compression of data plays a large
factor).  Your Symetrix at 40GB/hr is only 11.11MB/sec!  BTW, this is
with no unusual tuning to the system, since this was more than enough
performance for their needs.  With a little more tuning I could easily
increase that by 50% and possibly double it if I really tried and that
is ancient SSA technology.  FC technology should be much faster.

I know there are many people who prefer raw lvs for there disk pools,
but on an AIX system I don't believe it is worth it.  I have never had
anyone show me raw lv numbers on AIX that I could not match (with far
less hassle) with a good JFS2 configuration.  If raw is the way you want
to go than I wish you luck.  However, if you are interested in switching
to using a JFS2 approach I would be glad to post to the list some simple
guidelines for configuring your environment to get much better
performance than you are reporting in your post.

--
Regards,
Mark D. Rodriguez
President MDR Consulting, Inc.

===============================================================================
MDR Consulting
The very best in Technical Training and Consulting.
IBM Advanced Business Partner
SAIR Linux and GNU Authorized Center for Education
IBM Certified Advanced Technical Expert, CATE
AIX Support and Performance Tuning, RS6000 SP, TSM/ADSM and Linux
Red Hat Certified Engineer, RHCE
===============================================================================


Hart, Charles wrote:

Thanks you for the link.. Good info!


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]On Behalf Of
William F. Colwell
Sent: Friday, November 12, 2004 10:52 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: TSM and SATA Disk Pools


Charles,

See http://www.redbooks.ibm.com/abstracts/tips0458.html?Open

This was in a recent IBM redbooks newsletter.  It discusses SATA performance
and to me it says that the tsm backup diskpool is not a good use for SATA.
Sequential volumes on SATA may be ok.

Hope this helps,

Bill
At 10:21 AM 11/12/2004, you wrote:

Been asking lots of questions lately.  ;-)


We recently have put our TSM Disk Backup Pools on Clarrion SATA.
      The TSM Server is being presented as 600GB SATA Chunks
      Our Aix Admin has put a Raw logical over two 600GB Chunks to create a 
1.2TB Raw Logical Volume

Right now we are seeing Tape migrations @ about 4GB in 6hrs, where before on 
EMC Symetrix disk we saw 29-40GB per hour.  If anyone would like to share their 
TSM SATA Diskpool layout and or tips we would much appreciate it!!!


TSM Env
AIX 5.2
TSM 5.2.4 (64bit)
p630 4x4
8x3592 FC Drives

Regards,

Charles

----------
Bill Colwell
C. S. Draper Lab
Cambridge Ma.