[rabbitmq-discuss] Orphaned channels after connection close in Rabbit 3.1.4

Wed Aug 14 22:23:26 BST 2013

Paul,

On 14/08/13 10:41, Paul Bowsher wrote:
> After the upgrade to RabbitMQ 3.1.4 we're seeing a large number of
> linearly-increasing channels which seem to hang around after the
> connection is closed.

This is very unlikely to be related to the upgrade...

> - Initially, larger than expected consumer count on queue from our
> monitoring
> - Stopping all expected consumers on that channel removes the expected
> number of consumers, leaving orphans (700+ at present)
> - Each orphaned consumer's channel is reachable using Management tool
> - Each connection for the channel is reachable, is in either a "flow" or
> "blocked" state with zero data flow. Timeout is set to 600s (count
> doesn't decrease after 10 minutes)

The above is all consistent with connections being blocked due to 
resource alarms. Blocked connections do not get closed until they are 
unblocked. Check the server logs for alarm warnings.

> - Forcing a stuck connection closed through the management interface
> results in a 500:
>
>     The server encountered an error while processing this request:
>     {exit,{normal,{gen_server,call,
>                                [<0.16806.1347>,
>                                 {shutdown,"Closed via management plugin"},
>                                 infinity]}},
>            [{gen_server,call,3,[{file,"gen_server.erl"},{line,188}]},
>             {rabbit_mgmt_wm_connection,delete_resource,2,[]},
>             {webmachine_resource,resource_call,3,[]},
>             {webmachine_resource,do,3,[]},
>             {webmachine_decision_core,resource_call,1,[]},
>             {webmachine_decision_core,decision,1,[]},
>             {webmachine_decision_core,handle_request,2,[]},
>             {rabbit_webmachine,'-makeloop/1-fun-0-',2,[]}]}

That looks like a bug. Alas I cannot see anything obviously wrong in the 
code and I cannot reproduce it :( Is this easily reproducible for you?

Regards,

Matthias.