RE: SMP experiences

["Graap, Ken" <keg@xxxxxxxxxxxxx>]

Rick - 

We use SMP on our 730 8-way system and have for several years now. Elvis is
correct is indicating that it can be a bit aggressive with system resource
allocation sometime. We got around a major problem we were experiencing with
the building of temporary indexes as part of our regular morning sign on
into our CIS application, by changing system value QQRYDEGREE to *IO early
in the morning and them changing it back to *OPTIMIZE in the early
evening... This has worked very well.

We also installed a product (Centerfield's insure/RESOURCES) that intercepts
SQL and Query process requests and then executes the Change Query Attributes
(CHGQRYA) command allowing us to set the degree of parallel processing by
individual job. We have also discovered that it is very useful to utilize
the *NBRTASKS parameter of the CHGQRYA command to limit the number of tasks
to be used for SMP parallel processing. This give us more control than just
allowing the system to decided via the *OPTIMIZE or *MAX parameters.

If you have a lot of index rebuilds, SQL and query processes SMP will
provide you with a big performance boost. Personally, I think it should be
part of the base OS and not a chargeable feature. Especially in a world
where just about every iSeries is a multiprocessor system.

Kenneth

****************************************
Kenneth E. Graap
IBM Certified Specialist 
AS/400e Professional System Administrator
NW Natural (Gas Services)
keg@xxxxxxxxxxxxx
Phone: 503-226-4211 x5537
FAX:    603-849-0591
****************************************


-----Original Message-----
From: Elvis Budimlic [mailto:ebudimlic@xxxxxxxxxxxxxxxxxxxxxxxxx]
Sent: Tuesday, June 24, 2003 8:19 AM
To: 'Midrange Systems Technical Discussion'
Subject: RE: SMP experiences


Rick,

SMP will help Query Optimizer a great deal so if you are using lots of
SQL or OPNQRYF in your processing, you should see a notable performance
improvement. .....