VMS Alpha V8.2 Watchpoint utility broken

[David B Sneddon]

Hi Folks,

This question directly relates to the following thread

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=842851

but since no-one seems to want to take that one on...

The (unsupported) Watchpoint utility appears to be broken
on VMS/alpha V8.2.
Any access to the page containing the watchpoint causes a bugcheck.
I don't have the bugcheck code.

So my question, will a working watchpoint utility be
available sometime soon for V8.2?
This would make it easier to resolve my other problem by
identifying what is corrupting memory.

Regards
Dave

[David B Sneddon]

Correction.

I have found the utility is documented and I would
assume therefore supported.
I had always assumed it to be unsupported (don't
really know why there you go).
So my question still remains. Can we please have a
working copy?

Dave

[Volker Halle]

Hi,

I can confirm Dave's observation. WATCHPOINT is documented in the System Analysis Tools manual and as such should be supported.

Example: If you set a watchpoint to a location within a FCB, you'll get an INVEXCEPTN crash, if any memory location inside the page, in which the watchpoint has been set, is touched (even with a READ).

The condition code signalled is 00000414 = %SYSTEM-F-BREAK

Failing Instruction:
SEARCH_FCB_C+00910: LDL R27,#X008C(R12)

The page pointed to by R12 has a protection code of Read/Writ: KE-- NONE in the dump.

Volker.

[John Gillings]

Dave,

>Can we please have a working copy?

Please log a case, with a reproducer, so we can elevate it.

Thanks

[David B Sneddon]

John,

This is on my machine at home (hobbyist licenses) as mentioned in
the original thread about the UNXSIGNAL bugcheck.

Dave

[Robert Brooks_1]

Can someone with a support contract please log a call against the watchpoint utility? It really makes our lives much easier if these things are initiated by a paying customer.

-- Rob

[John Abbott_2]

We pay & have 8.2 but not currently installed. Big question: Is there enough info. in this thread for me to pass it on without 20 more questions or needing a dump?
What 8.2 patches are installed ? On what hardware ?

PS. Would like these things fixed before we go there!

Kind Regards,
John.

[David B Sneddon]

John A,

If you have a look through the other thread mentioned above
you will see the origins of this thread.
Since this problem arose whilst trying to determine the
cause of the UNXSIGNAL bugcheck in the other thread, and
it seems to be fairly specific to my hardware configuration
there is a good chance that you will have no problems, unless
of course you try to use the Watchpoint utility.
The issue with the Watchpoint utility seems to relate
to V8.2 and not my hardware (as mentioned by Volker).
I also have 8.2, and support, at work but have not yet
installed it because we use shadowing and I don't want
to potentially screw up any machines at work until I
can resolve the UNXSIGNAL bugcheck issue.
I also don't have a spare machine with which to play at present.
The system in question was upgraded from 7.3-2 to 8.2
and the two current ECOs installed.
It is a Digital Personal Workstation 600au.

Dave

[Robert Brooks_1]

I've asked around within VMS Engineering about the problems with the Watchpoint utility.
This is what I've heard so far . . .

"There's a number of known problems with its current implementation.
In particular, it doesn't work on any SMP system. [name deleted] has a Nemo [V8.3] work item to fix/overhaul it and to port it to I64."

So, there's no need to file an official work request to get the ball rolling. I don't know if the V8.3 work will be backported to V8.2 or not; that decision will be made later.

Has anyone tried the watchpoint utility on a single-CPU system?

As always, thanks for letting us know about this problem!

-- Rob

[David B Sneddon]

Rob,

The machine at the heart of this problem is a single-CPU
Digital Personal Workstation 600au...
so in answer to your question -- yes.

(Also, the $WP*DEF macros described in the manual do not
exist in LIB.MLB on V8.2, or as far back as V7.1-2. Is this
an oversight or are they hidden away somewhere else?)

Regards
Dave