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My code contains a loop that has to perform calculations on data

streamed from a circular buffer. The calculation has to be performed

50,000+ times (about 30 ms per cycle) spitting out a number after each

cycle. The thing freezes in a poissonic manner (i.e. sometimes after 10

seconds of data aquizition, sometimes after 10 min of data aquizition,

etc). I do have the debugger attached. The program just stops

responding and I only can terminate it by "Debug->Stop debugging".

There are no indiciations in the Debug output window which would warn

me of the onset of the freeze. Since the freeze happens randomly, and I

don't see any feedback in the debugger, I am puzzled how I can

systematically debug this thing. Can anyone give a spepific advice on

where I could start?


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Sorry, I should've said I am using .NET and MFC.



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revyakin@yahoo.com wrote:

You can also do Debug | Break All and see what the code was doing at

the time.

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With best wishes,

Igor Tandetnik



With sufficient thrust, pigs fly just fine. However, this is not

necessarily a good idea. It is hard to be sure where they are going to

land, and it could be dangerous sitting under them as they fly

overhead. -- RFC 1925





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Call stack is going to be the best thing for you here IMO.



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- Mark Randall

zetech.swehli.com">zetech.swehli.com



"Those people that think they know everything are a great annoyance to those

of us who do"

Isaac Asimov

<revyakin@yahoo.com>wrote in message



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Thanks a lot, Igor and Mark. I found a library file that was causing

this behavior using the call stack.



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even though I found what causes the trouble, Interestingly, I found

that both the stack call and the break call don't always point to the

actual process/dll causing the problem. I wonder what it means.



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<revyakin@yahoo.com>wrote in message

There are probably several threads. Your code is on one of them, some

unrelated system code runs on the others. Open Threads window, find your

primary thread, switch to it and you'll get correct call stack.

--

With best wishes,

Igor Tandetnik



With sufficient thrust, pigs fly just fine. However, this is not

necessarily a good idea. It is hard to be sure where they are going to

land, and it could be dangerous sitting under them as they fly

overhead. -- RFC 1925





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On top of what other have suggested, the best way to debug

these configuration, is in my opinion, the non-invasive debugging

offered by the system debuggers cdb/ntsd/windbg.

You can attach non invasively a debugger to a hung process,

even if it's being alreadu debugged by devenv.exe.

c:\debuggers>cdb -pv -p <pid>

the, from the debuggers prompt, you can inspect the stack of all the

threads,

with `~*kb`, and, the running time as well, with `!runaway`.

If you post the output of the two previous commands on the forum,

with good symbols, most likely people would be able to help.



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<revyakin@yahoo.com>wrote in message



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