Look to the Share Proceedings for Tom Berevtas' presentations on the best I/O from FICON. Watch out about using PDSEs on very large active (members being written) Libraries. Check Cheryl Watson's Newsletter for a very detailed report from the last Share. CA-PMO and CA-PDSMAN has been used at several large sites to successfully help with I/O elimination.
-----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Knutson, Sam Sent: Wednesday, June 15, 2005 SYSN 6:06 PM To: [email protected] Subject: Re: Disk I/O tuning still possible? Disk I/O Tuning is absolutely possible and in fact is the single biggest opportunity we have in most cases. DFSMSdfp options offer a great many choices to increase the performance with system managed buffering, compression, stripes, and more. Compression is a space utilization and performance enhancement with data like SMF records, SVC dumps, and other data with easily compressed content. I use compressed and striped on all the intermediate files dumped from the SMF MANX datasets and it works great reduced processing time to about 1/4 of what it was. Chuck Hopf has this and some other great tips in his MXG presentation. If you use MXG or don't it's still some great information on how to handle processing lots of SMF data. Visit http://www.mxg.com/downloads.asp and scroll down to "MXG Simplified (2004) Chuck Hopf" to download a copy. It sounds like you are still on ESCON channels. If you can spend some money rather than buying more ESCON channels start trying to figure out how you can migrate to FICON channels. The best I/O is of course no I/O so look at the opportunities to eliminate stupid I/O with bad block sizes you can fix, repetitive PDS I/O you can eliminate by using PDSE or LLA when you cannot change the program, etc. Best Regards, Sam Knutson, GEICO Performance and Availability Management mailto:[EMAIL PROTECTED] (office) 301.986.3574 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
