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Viv Bassani wrote: > > We currently have a single processor 50S #2122 running V3R7 > There is a requirement to run a high CPU/IO intensive batch > job which has a totally dedicated system. We have run the job > on the 50S and we are achieving around 100 records per hour. As > this machine is not powerfull enough for the task we now have a > new option. > A couple of years ago, in an IBM AS/400 Newsletter, was a description on using data queues to sysnc a disk prefetch for long running batch jobs. There were some dramatic reductions in run time. (based upon the actual application your mileage may vary). In a nutshell here is how it works: Your main program has some sort of primary file it is processing and doing CHAIN/READ along the way. In a separate storage pool, you start a prefetch job which also processes the same file, skips the first record and does the chain(s) for the second record. It basicly stays one record ahead of your main program. It waits on the data queue to know that your main program is starting record two so the prefetch starts record three. The main program benefits by overlapping it's computations with the prefetch programs disk I/O so that when the main program does a disk request the record is already in cache. You can clone the main program, gutting it's calculations, add the data queue wait and you have the prefetch program. It might be worth spending a day giving it a try. James W. Kilgore QAPPDSN@ibm.net * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * This is the Midrange System Mailing List! To submit a new message, * * send your mail to "MIDRANGE-L@midrange.com". To unsubscribe from * * this list send email to MAJORDOMO@midrange.com and specify * * 'unsubscribe MIDRANGE-L' in the body of your message. Questions * * should be directed to the list owner / operator: david@midrange.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
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