Well Alan, as you've, "Opened the floor for discussion" - here's my two 

penn'orth on how I think it SHOULD work.

I think we're all pretty-much agreed on Virtual R/R support within a 
single VM image, it's when to issue a REAL R/R that's the sticking-point.


I would contend that a REAL R/R should be issued whenever the virtual R/R
 
is honoured on ANY minidisk associated with a real volume (that supports 

real R/R) that's under control of cross-system link (aka XLINK) or 
whenever the subject minidisk begins on real cylinder zero.

I would like to retain the "V" appendage to explicitly tell CP which 
minidisks are subject to virtual R/R support because this would protect m
e 
from, "denial of service" behaviour based on someone realising that their
 
CMS minidisk is on a cross-system-linked disk and that they can therefore
 
mess things up by issuing a RESERVE CCW. However, this is unlikely enough
 
that I'd be willing to be persuaded that CP should simply honour all R/R 

activity on all minidisks under the scheme outlined above. (Maybe relocat
e-
zero should imply, "V" but it needs to be explicitly coded on non-relocat
e 
zero?)

While I was at it, I would also extend the automatic assignment of SHARED
 
status to any real volume that's put under XLINK control at the time that
 
it's ATTACHED to SYSTEM, with (of course) the option of using the 
appropriate SET command to change this to cater for, "unusual" 
circumstances. I find the current mechanisms for establishing SHARED 
status on real packs tiresome - and it'd be so natural to assume shared 

for XLINK packs.

OK, let's see what others think :-)

Regards
Jeff Gribbin

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