RE: Automatic Performance adjustment

["Ingvaldson, Scott" <SIngvaldson@xxxxxxxxxxxx>]

I can answer this one, if you look at WRKSHRPOOL and do an F11 to display
the Tuning Data, you'll see that the minimum percentage of storage for the
interactive pool is probably set to 10% (200 MB)  You can manually change
the pool to 50 MB, but it will move back up to the minimum no matter what
the workload is.  You need to change the minimum percentage to a lower value
to get it to stay down.

Scott Ingvaldson
AS/400 System Administrator
GuideOne Insurance Group

-----Original Message-----
date: Mon, 3 Mar 2003 11:00:16 -0600
from: "Jones, John (US)" <John.Jones@xxxxxxxxxxxxxxxxxxxxxxx>
subject: RE: Automatic Performance adjustment

I still see the performance adjuster doing odd things even at V5R1
CUM2134.  

Example:  It's a Saturday and I'm doing some maintenance on our dev box
(720).  I'm the only user signed on and I've submitted some big batch
jobs.  While waiting for the batch jobs to finish, I'm occasionally
hitting F10 on a WRKACTJOB and/or WRKSYSSTS display.  With the perf
adjuster on, my activity will be allocated about 200MB of main storage
with the remainder being split between *MACHINE & *BASE.  The box has
2GB total.  Page faulting in *MACHINE will be higher than in *BASE.  So
I drop *INTERACT to 50MB but over time it moves it back up.

There's no reason for a single interactive job that uses under 2% of the
CPU load to be allocated 10% of main storage, especially when the
program stack isn't really changing and I'm only refreshing the display
every couple of minutes.

I manually tune our production system, but leave the dev box at
QPFRADJ=3 to see if the auto tuner improves as new PTFs/releases are
loaded.

- John