Ask the EMC vendor if the Subsystem has dynamic Parallel Access Volumes (PAV's) turned on assuming the EMC Subsystem supports it. This creates multiple volumes for one. Puts the water where the fire is.
-----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Jousma, David Sent: Monday, January 23, 2012 9:18 AM To: IBM-MAIN@bama.ua.edu Subject: Re: Going from mod-3 to mod9 Iosq? Really? This is raid dasd, isn't "slow" 3390-9's a thing of the past? _________________________________________________________________ Dave Jousma Assistant Vice President, Mainframe Services david.jou...@53.com 1830 East Paris, Grand Rapids, MI 49546 MD RSCB2H p 616.653.8429 f 616.653.2717 -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Staller, Allan Sent: Monday, January 23, 2012 10:09 AM To: IBM-MAIN@bama.ua.edu Subject: Re: Going from mod-3 to mod9 <snip> 1. We just had 3390-9's configured into our EMC box. This box also contains 3390-3's. Given that the hardware is the same throughout and all other things being equal, is there any decrease in response time on the mod-9's? </snip> Beware of IOSQ! From the viewpoint of the Operating System, you now have 3 times as much data behind the actuator on Mod-9's as Mod-3's. If the Operating system *thinks* the device is busy, the IO is queued off the UCB and never even tried until it comes to head of queue. Multi-system access will exacerbate this even more. <snip> 2. I have a VSAM file (with extended addressability) that currently spans 27 mod-3's. My plan is to move it to 10 mod-9's using IDCAMS REPRO to back it up then doing a DELETE/DEFINE, (changing the SPACE parameter from CYL(2500 150) to CYL(9500 150)), then REPRO from the backup. Am I setting myself up for a failure? </snip> I do not believe there will be an issue. Obviously, you already have all of the SMS stuff in place. I would, however suggest REPRO from "original" to "original.new" and after successful repro operation, alter "original" to "original.old" and then alter "original.new" to original". In this way, the original is always available for a momentary recover if any problems are discovered with the target of the repro. This e-mail transmission contains information that is confidential and may be privileged. It is intended only for the addressee(s) named above. If you receive this e-mail in error, please do not read, copy or disseminate it in any manner. If you are not the intended recipient, any disclosure, copying, distribution or use of the contents of this information is prohibited. Please reply to the message immediately by informing the sender that the message was misdirected. After replying, please erase it from your computer system. Your assistance in correcting this error is appreciated. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
