On Wednesday, 09/06/2006 at 01:10 AST, "Wakser, David" <[EMAIL PROTECTED]> wrote: > I believe it is probably overhead that should be avoided? But even if that is > not the case, why buy bicycle tires if you have no bicycle?
For clarity: - The "V" enables CP simulation of RESERVE/RELEASE for guests on the *same* VM system. Without it, CP causes a Command Reject on the RESERVE or RELEASE (resulting the VSE message) - IF a minidisk link mode has the "V" on it AND it is full-pack (not just starting on cyl 0) AND it is defined as SHARED THEN CP will propagate a RESERVE/RELEASE to the real DASD volume. The "V" is optional to allow continued simulation of older dasd configuration that don't have the then-optional "two-channel switch" feature. You *do* have 2835 and 3880 control units, right? :-) Back then on the real dasd you would get a Unit Check with Command Reject. You get the same thing on a minidisk without the "V". [20 years pass] So, it is now the 21st century and Walter Cronkite no longer hosts the CBS Evening News. Should we change CP such that "V" is the "unchangable default"(SM)? Is there any reason RESERVE/RELEASE should remain disabled in an ECKD world? (VM no longer supports CKD devices, where RESERVE would be optional.) If the disk is a full-pack mini, should CP treat the volume as if it were defined as SHARED? The floor is open for discussion. Alan Altmark z/VM Development IBM Endicott
