Hi

How is your 660 configured?

How many FC adapters are installed, and do you have 1 or 2 I/O drawers?

How is the adapters placed within the I/O drawer(s)?

Is the disk and tape connected through the same FC adapters?

How many mounts are made during step 1 and 2? 

Best Regards

Daniel Sparrman
-----------------------------------
Daniel Sparrman
Exist i Stockholm AB
Propellervägen 6B
183 62 HÄGERNÄS
Växel: 08 - 754 98 00
Mobil: 070 - 399 27 51




"Thach, Kevin" <KThach AT COVHLTH DOT COM>
Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
2002-11-07 16:47
Please respond to "ADSM: Dist Stor Manager"

 
        To:     ADSM-L AT VM.MARIST DOT EDU
        cc: 
        Subject:        Daily Processing Performance (very slow - any ideas?)


I'm very dissapointed with the performance of our TSM environment, and I 
was
curious what kinds of numbers some of you with similar environments have
experienced.  I've worked extensively with IBM to try and tune things, but
apparently we've got everything adjusted correctly.  We are in the process
of cleaning up System Object stuff, so I'm wondering if I should expect
things to improve dramatically once we trim all that fat.

I apologize for the lenght of the post, but I want to include as much info
as possible.  I'm in dire need of a solution.

Our basic setup:

IBM 6H1 - 6 Processors / 4GB RAM
TSM 4.2.3 on AIX 4.3.3-09

LTO 3584 Tape Library with 10 drives
Fiber-arbitrated loop going through McData ES-1000 switches and McData 
6064
Directors

500GB Non-Collocated Disk Pool on ESS
250GB Collocated Disk Pool on ESS
37GB TSM database

Approximately 200 Clients (mixture of AIX and WinNT/2K) running at various
client versions

200GB total / night backed up on average.

Daily Processing is slow, slow, slow.

Here are the steps for our daily processing (its all scheduled, but I'm 
just
showing you what runs when):

1) 7:00:00 - Daily processing starts
backup stg nocodisk copypool maxproc=4 wait=yes
backup stg colodisk copypool maxproc=4 wait=yes

2) Once that is finished the migrations start (I have the maxproc on both
pools set to 5)
update stg nocodisk hi=0 lo=0
update stg colodisk hi=0 lo=0

3) Once Migration is finished
update stg nocodisk hi=90 lo=70
update stg colodisk hi=90 lo=70
backup stg nocotape copypool maxproc=3 wait=yes
backup stg colotape copypool maxproc=3 wait=yes

4) Once that is finished
expire inventory

5) Once that is finished
backup db devclass=ltotape type=full

6) Then
backup volhist
backup devconfig
prepare

So, the big disappointment is on steps 1 and 2.  Our disk to tape
performance averages about 20GB/hour per tape drive.  If I reduce the 
number
of mount points, that number goes down even more.  Are LTO's really this
slow?  IBM says these suckers will do 50-100GB/hour.  With 10 drives, we
were told we could handle about 1-2 TB/day, and we're only dealing with
200GB and the entire daily processing takes more than 6 Hours!!!

At one time we were using disk caching, and I was told that slowed down 
disk
to tape performance, so we turned it off.  I saw a slight improvement, but
nothing major.  The Noncollocated disk pool still has data in it that has
not expired yet since I turned off caching.  Could that still be slowing
things down if the pool isn't completely flushed?

What can I really expect to get as far as performance?  How long should
daily processing really take for only 200GB worth of data?

Any help is greatly, greatly appreciated!

Thanks!
-Kevin

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