I would argue the OEM tools are not any better (or worse for that matter)
than the IBM auto tuning feature, and IBMs is free. But consider ALL of the
auto tune products. They are a lot like driving down the road using nothing
but your left rear view mirror. You'll get where you are needing to go.
Not as safely as looking forward but you'll get there. Here's the key, you
are always looking at what just happened, not what is happening now, and
going to happen. That's auto tune.
In some shops that might work very well, Paul and a few other report great
success, wonderful, keep doing it. For those with work loads that vary too
fast for auto tune, the best solution is more memory, so you can tune for
the peaks/valleys.
--
Jim Oberholtzer
Agile Technology Architects
-----Original Message-----
From: MIDRANGE-L <midrange-l-bounces@xxxxxxxxxxxx> On Behalf Of Rob Berendt
Sent: Monday, December 03, 2018 1:42 PM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
Subject: RE: DB2 Symmetric Multiprocessing (option 26 of 5770SS1) Was:
Performance tuning
There are 3rd party tools out there for a more responsive shift. I have no
familiarity with them.
Keep in mind Jim's concerns with SQL optimization vs frequent performance
changes. But, perhaps one big shift is better then frequent smaller shifts.
Rob Berendt
--
IBM Certified System Administrator - IBM i 6.1 Group Dekko Dept 1600 Mail
to: 2505 Dekko Drive
Garrett, IN 46738
Ship to: Dock 108
6928N 400E
Kendallville, IN 46755
http://www.dekko.com
From: "Steinmetz, Paul" <PSteinmetz@xxxxxxxxxx>
To: "'Midrange Systems Technical Discussion'"
<midrange-l@xxxxxxxxxxxx>
Date: 12/03/2018 02:34 PM
Subject: RE: DB2 Symmetric Multiprocessing (option 26 of
5770SS1) Was: Performance tuning
Sent by: "MIDRANGE-L" <midrange-l-bounces@xxxxxxxxxxxx>
Rob,
< IBM's tool only readjusts small chunks at a time, spread out over quite
some time period. Which may not be near responsive enough if you've just
dropped QINTER to start your month end, as just one example.
I've seen this behavior, which is not always satisfactory.
IBM auto tune adjusts approximately every 20 seconds, approximately 5k
chunks.
What do you recommend?
What are some alternatives?
Paul
-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Rob
Berendt
Sent: Monday, December 03, 2018 1:24 PM
To: Midrange Systems Technical Discussion
Subject: RE: DB2 Symmetric Multiprocessing (option 26 of 5770SS1) Was:
Performance tuning
There are a few of schools of thought on auto tuning.
One is that, in a 'more than light' SQL shop one should not use autotuning
as it forces the sql optimizer to recalculate.
Another is that auto tune at IPL time may be appropriate, to start taking
advantage of new memory added to the system.
Another is that a light to no sql shop could use IBM's autotuning and be
happy.
Another is that IBM's autotuning is too gradual and one should use a more
responsive 3rd party product.
IBM's tool only readjusts small chunks at a time, spread out over quite
some time period. Which may not be near responsive enough if you've just
dropped QINTER to start your month end, as just one example.
Rob Berendt
midrange.com
