<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. HTH, ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN