RE: Subsystem and memory pools

I'm a firm believer in auto adjustment. QPFRADJ = 2.
Agree, memory is moved in small chucks, little at a time, which sometimes is bad.
Also a firm believer in a fewer number of pools, I only have 5.
My paging numbers (from MPG) are good, so I feel the configuration is good.

Majority of our batch work runs off shift, after 5, before 8, *SHRPOOL1.
If no batch work is running, that memory is released back to *BASE, which then in turn is available for *INTERACT.

From 8 to 5, *INTERACT for 5250 takes the memory from *BASE, as needed.

These rules have been in place for decades.

But now we have more background jobs, (IVR, Interfaces, Credit Card system, DOMO Replication, Halcyon monitoring, Robot Scheduler), that are constantly running, serving both batch and/or interactive.

How should these be considered,
batch-*SHRPOOL1
interactive-*INTERACT
or leave in *BASE.

Paul

-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Rob Berendt
Sent: Friday, December 15, 2017 10:17 AM
To: Midrange Systems Technical Discussion
Subject: Re: Subsystem and memory pools

The classic answer "it depends".

Do you have auto adjustment set on your pools? Some argue that it's a good thing, why waste memory in a pool that's currently under utilized.
Some might argue that IBM's auto adjuster is not robust enough and cautiously only moves small chunks at a time.
Some might argue that changing your pool sizes too often forces the query optimizer to notice the environment changed and reoptimize your queries.
Some might say that if you're going to do this they you really need to look at
WRKSHRPOOL
F11=Display tuning data
and set a minimum size to keep others from stealing too much from a pool.

Where do activities fall in priority? For example, are you still using a bunch of 5250 applications? Should they get priority over the application? Do you lump 5250 in with "interactive" work performed by the application?

Are there other tuning considerations which may cause consideration to other pools? For example, fixed vs calc paging, max active, faulting settings, etc.



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: 12/15/2017 10:03 AM
Subject: Subsystem and memory pools
Sent by: "MIDRANGE-L" <midrange-l-bounces@xxxxxxxxxxxx>



Reviewing some subsystems that were created by 3rd party applications.
By default, they run system pool 2, *BASE.
Normally I have *BASE for system usage only.

All my interactive work runs in system pool 4, *INTERACT.
All my batch work run in system pool 5, *SHRPOOL1

3rd party applications, which are constantly running, where should they
reside, *INTERACT or *SHRPOOL1?


System Pool Reserved Max
Pool Size (M) Size (M) Active Pool
1 17344.7 2872.0 +++++ *MACHINE
2 65406.2 14.5 1346 *BASE
3 1576.7 2.5 51 *SPOOL
4 30376.1 .1 3141 *INTERACT
5 42975.9 <.1 30 *SHRPOOL1

Thank You
_____
Paul Steinmetz
IBM i Systems Administrator

Pencor Services, Inc.
462 Delaware Ave
Palmerton Pa 18071

610-826-9117 work
610-826-9188 fax
610-349-0913 cell
610-377-6012 home

psteinmetz@xxxxxxxxxx
http://www.pencor.com/