VW 7.7: Couldn't signal a delay semphore

> Hi,
>
> One of our customers has a problem where our application blocks after
> running for several hours or days. The reason for this is not clear to
> us. All that is visible on screen is that the application is “not
> responding” anymore.
>
> In one instance, the following dialog box appeared:
>
> What could be the cause of this error?
>
> They are using vw7.7 and they run the application on a “Windows 2008
> Server, Service Pack 2, 64bits”. The application is 32 bit.
>
> Thanks,
>
> Mark
>
>
>
> _______________________________________________
> vwnc mailing list
> [hidden email]
> http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

> Hi,
>
> One of our customers has a problem where our application blocks after
> running for several hours or days. The reason for this is not clear to
> us. All that is visible on screen is that the application is "not
> responding" anymore.
>
> In one instance, the following dialog box appeared:
>
> What could be the cause of this error?
>
> They are using vw7.7 and they run the application on a "Windows 2008
> Server, Service Pack 2, 64bits". The application is 32 bit.
>
> Thanks,
>
> Mark
>
>
>
> _______________________________________________
> vwnc mailing list
> [hidden email]
> http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

> Hi Andres,
>
> Thanks for the reply.
>
> Apart from investigating why the image hangs, to which version of the VM should we upgrade? We're using vw7.7 right now. Would 7.7.1 contain the fix you mention?
>
> Mark
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]] On Behalf Of Andres Valloud
> Sent: maandag 9 mei 2011 21:22
> To: [hidden email]
> Subject: Re: [vwnc] VW 7.7: Couldn't signal a delay semphore
>
> In some circumstances you can get this error from earlier VMs.
> Basically the issue is that if the VM is locked (e.g.: during a DLLCC
> call) for a long time, then signals coming into the VM will overflow the Windows delay semaphore set to catch the incoming signals.
>
> When the delay semaphore is created, you have to say how many signals it can hold.  The semaphore is there so the VM can go to sleep on it when it has nothing to do.  It's only necessary to catch one signal to wakeup the VM, because it will wake up the VM just as well as many.  We could have increased the already high limit some more, but that would have just hidden the bug from view.  The fix is to stop accumulating signals.
>
> It seems the problem you describe is the same we fixed before.  I'd suggest upgrading your VMs, we had a customer with the same problem and the fix resolved their issue.  You may still have to investigate why the application hangs.  I'd suggest using WinDBG on the hung VM and calling
>
> dumpAllToFile(0, 1);
>
> This will produce a file called stack.txt with a description of what's going on in the image.  You may have to do that on a VM that has enough debugging information so that the debugger can find dumpAllToFile().
>
> On 5/9/2011 5:04 AM, Mark Plas wrote:
>> Hi,
>>
>> One of our customers has a problem where our application blocks after
>> running for several hours or days. The reason for this is not clear to
>> us. All that is visible on screen is that the application is "not
>> responding" anymore.
>>
>> In one instance, the following dialog box appeared:
>>
>> What could be the cause of this error?
>>
>> They are using vw7.7 and they run the application on a "Windows 2008
>> Server, Service Pack 2, 64bits". The application is 32 bit.
>>
>> Thanks,
>>
>> Mark
>>
>>
>>
>> _______________________________________________
>> vwnc mailing list
>> [hidden email]
>> http://lists.cs.uiuc.edu/mailman/listinfo/vwnc
> _______________________________________________
> vwnc mailing list
> [hidden email]
> http://lists.cs.uiuc.edu/mailman/listinfo/vwnc
>