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Ken, If you have Performance Tools, run some of the performance reports and look at the exceptions analysis. Also, you may want to create a BEST/1 model from some collected data and then play with the model. You can reallocate the memory pools and see predicted results, although predictions and the real world have a habit of being different. But, it's one way to play without 'hurting' your production environment. You can then try making the changes for real and measure the results. Your 'slowdowns' may have nothing to do with memory or disk, perhaps record locking, or comm waits, or ..... Glenn -----Original Message----- From: Graap, Ken [mailto:keg@exchange.gasco.com] Sent: Monday, May 22, 2000 11:34 AM To: 'Midrange' Subject: Using OS/400 AutoTuner We have one system supporting, production and development. It is difficult to determine what kind of work will be submitted or run interactively at any particular time. In order to insure optimum memory allocation between storage pools, I am using the OS/400 AutoTuner (QPFRADJ=3). We have 16GB of RAM on our Model 730 and are at V4R4. During the day I see as high as 10GB memory allocations between pools, usually *Shrpool1 AND *Interact... The pools are defined as follows: Defined Max Allocated Pool -Paging Option-- Pool Size (M) Active Size (M) ID Defined Current *MACHINE 895.17 +++++ 895.17 1 *FIXED *FIXED *BASE 1638.40 72 1638.40 2 *CALC *CALC *INTERACT 7807.52 30 7807.52 4 *CALC *CALC *SPOOL 81.91 15 81.91 5 *FIXED *FIXED *SHRPOOL1 5960.98 15 5960.98 3 *CALC *CALC Batch work runs in SHRPOOL1. I'm currently trying to figure out why we are experiencing periodic system slowdowns even though our CPU utilization averages less than 20%, disk arm utilization around 5% and faulting around 10-20 per second in *INTERACT and *SHRPOOL, most of that being DB Faulting. I'm able to control the memory allocation swings somewhat using the WRKSHRPOOL command interface: -----Size %----- -----Faults/Second------ Pool Priority Minimum Maximum Minimum Thread Maximum *MACHINE 1 5.48 100 4.00 .00 6.00 *BASE 2 10.00 85.00 10.00 2.00 100 *INTERACT 2 25.00 85.00 5.00 .50 200 *SPOOL 4 .50 3.00 5.00 1.00 100 *SHRPOOL1 3 10.00 85.00 10.00 2.00 100 I change the Minimum values to control how much storage is available to reallocate.... I would prefer not to restrict memory allocation too much, because it can result in substantial amounts of memory being left in a pool that isn't being used. I would like to give the OS/400 tuning algorithm as much control as possible over tuning, as long as it doesn't prove to be detrimental to interactive response times or batch throughput. I would suspect that large (10GB or more) memory reallocation might result in some slowdown for interactive users as pages originally resident in RAM are being written to disk, but could this be causing my system to slow down significantly? Any thoughts or comments are welcome. I'm just exploring possibilities... Kenneth **************************************** Kenneth E. Graap IBM Certified Specialist AS/400 Professional Network Administrator NW Natural (Gas Services) keg@nwnatural.com Phone: 503-226-4211 x5537 FAX: 603-849-0591 **************************************** +--- | This is the Midrange System Mailing List! | To submit a new message, send your mail to MIDRANGE-L@midrange.com. | To subscribe to this list send email to MIDRANGE-L-SUB@midrange.com. | To unsubscribe from this list send email to MIDRANGE-L-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: david@midrange.com +--- +--- | This is the Midrange System Mailing List! | To submit a new message, send your mail to MIDRANGE-L@midrange.com. | To subscribe to this list send email to MIDRANGE-L-SUB@midrange.com. | To unsubscribe from this list send email to MIDRANGE-L-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: david@midrange.com +---
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