On Wednesday, 04/06/2005 at 11:36 EST, Tom Duerbusch <[EMAIL PROTECTED]> wrote: > I doubt we have device queuing on CP-owned volumes.
If you aren't getting queues, then PAV will provide no benefit. The primary reason PAVs exist is to provide relief to fully-populated z/OS systems with 256 chpids and 64K devices. In such configurations the dasd has no choice but to get bigger and bigger. Because of the high-volume database transactions common to z/OS systems, PAVs are used to minimize the latency introduced by device queuing. As I said, I'm not against PAVs on moral grounds or anything, I just want to be sure that everyone asking for PAV support for CP-owned volumes (minidisks, paging, spooling) realize what problem it is meant to solve. If there's contention on a volume with minidisks, VM at least lets you move the minidisks around to let you manage the performance. I.e. we can solve it administratively instead of with technology. It's been a lively discussion! Alan Altmark z/VM Development IBM Endicott ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
