[zeromq-dev] Pub/sub, inproc shutdown Assert failure

[Martin Hurton]

I will look into it. Thanks!

- Martin

On Mon, Jun 11, 2012 at 2:23 AM, hp010170 <hp010170 at gmail.com> wrote:
> Marc, Martin:
>
> I am not sure if this is related, however, I have observed that:
>
> 1. tests/test_shutdown_stress.cpp seg-faults on seemingly random runs
> 2. test_shutdown_stress uses PUB/SUB
> 3. test_shutdown_stress does uses tcp:// instead of inproc://
>
> To illustrate:
>
> --x--x--
> hp $ for i in {1..20}; do ./tests/test_shutdown_stress; done
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> Segmentation fault
> test_shutdown_stress running...
> test_shutdown_stress running...
> test_shutdown_stress running...
> Segmentation fault
> --x--x--
>
> As you can see, I am not able to make out a pattern from a precursory
> glance.  I haven't plugged in the debugging tools yet, this was just
> from regularly building the code, I noticed the issue.
>
> The above is from the latest libzmq in the repository.
>
> Let me know if I can provide any more information.
>
> -HP
>
> On 10/06/2012 18:39, Martin Hurton wrote:
>> Hi Marc,
>>
>> 1) could you create an issue
>> 2) could you put together minimal C program reproducing this bug and
>> make pull request so it finds its way into issues repo
>>
>> Thanks, martin
>>
>> On Sat, Jun 9, 2012 at 9:19 PM, Marc Criley <mcriley.1979 at gmail.com> wrote:
>>> I'm getting:
>>>
>>> Assertion failed: ok (mailbox.cpp:79)
>>>
>>> when trying to shut down my application. After having searched the archives
>>> and whitepapers I'm still at a loss. Here's the structure of what I have and
>>> am trying to do (version 2.1.9-1, distributed with Ubuntu):
>>>
>>> - One main thread establishes a PUB socket using the 'inproc' transport.
>>> - Four separate threads each open a SUB socket.
>>> - 'inproc' requires the pub and sub sockets to use the same context, so that
>>> is done.
>>> - Each subscriber socket waits on 'recv()' for something to arrive, which is
>>> then processed, and returns back to waiting for the next message.
>>>
>>> Everything runs fine in the application. However, at shutdown:
>>>
>>> - There is no pending traffic, it has all been cleared.
>>> - The main thread closes its PUB socket.
>>> - The main thread invokes zmq_term, which blocks.
>>> - This unblocks the four subscriber threads waiting on recv().
>>> - Each subscriber thread closes its socket and the thread terminates.
>>>
>>> At this point I expect the main thread call of zmq_term() to complete.
>>> That's not what happens, instead I get:
>>>
>>> Assertion failed: ok (mailbox.cpp:79)
>>>
>>> I believe I did this in accordance with the 0MQ Termination whitepaper
>>> (http://www.zeromq.org/whitepapers:0mq-termination), and this is the
>>> sequence I use to shutdown a tcp transport client thread, which works
>>> without problem.
>>>
>>> Deferring closing the PUB socket until after zmq_term doesn't work, as
>>> zmq_term blocks until the socket is closed.
>>>
>>> Any suggestions would be appreciated.
>>>
>>> Marc C
>>>
>>>
>>> _______________________________________________
>>> zeromq-dev mailing list
>>> zeromq-dev at lists.zeromq.org
>>> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>>>
>
>
> _______________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> http://lists.zeromq.org/mailman/listinfo/zeromq-dev