I have to agree with Jeff. The hung user situations that we have had are not 
unsolved because of the lack of trying to diagnose them by IBM and other 
vendors. The nature of the beast is that the culprit has vanished into the 
night before anyone notices that there is a problem. It is the classic case of 
it being so long after the actual occurrence of the problem that all clues have 
been obliterated. Both IBM and VSSI (the vendor of VPARS, the program product 
that might possibly cause our hangs) have pored over several dumps and found 
nothing more than what I could find. The dumps were taken too far after the 
actual hanging of the user. To be sure, it is difficult to imagine being able 
to take the dump at the best moment for determining what went wrong. For 
example, a check to insure that the count goes to zero when the last item of 
deferred work completes may, probably will, be too late. It may have been an 
earlier task that failed to decrement the count. This is a problem that can 
only be detected long after it has happened. It is much more difficult to catch 
a problem when something doesn't happen than it is to catch it at the time it 
happens.


 -----Original Message-----
From:   VM/ESA and z/VM Discussions [mailto:[EMAIL PROTECTED]  On Behalf Of 
Jeff Gribbin, EDS
Sent:   Tuesday, December 20, 2005 12:12 AM
To:     [email protected]
Subject:        Re: forcing a user

Hello Thomas,
I have to disagree with your comment about IBM VM Development's attitude 
to HUNGUSER situations. In my experience IBM has been obsessive about 
eliminating all possible HUNGUSER situations and will ALWAYS follow up any 
documented HUNGUSER reports. In my view VM Development is fully aware of 
the impact of a VM IPL - and this awareness has been a significant 
contributor to VM's intrinsic reliability - VM reliability has never been 
compromised merely for the sake of function - sometimes to the frustration 
of those eagerly awaiting that function - but, in my view, the only 
realistic strategy if there's to be a future.

I guess you're right - it was a bad weekend.

Regards
Jeff Gribbin (Speaking for myself)

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