On 07/25/2011 10:54 AM, Ilyushonak Barys wrote:
Could you please help me with the following issue. I have static exchange route from source broker (S) to destination (D). It works fine until network problems occurred. If the connection between S and D is broken (firewall for example), I have internal private queue overflow on the source (S) broker. Is it expected behavior?
Not entirely... exchange routes use temporary queues and non-reliable transfer (i.e. messages are dequeued as soon as they are transferred).
That should mean that while the connection is considered open by the source broker it will continue to send messages. When the connection is considered closed it will delete the queue entirely.
However the writing out of messages is enabled by the socket being writeable. So possibly if the socket is not detected as closed, but is not writeable either, then messages could not be sent and the queue would back up eventually reaching its limits.
Heartbeats are enabled (and hardcoded at present) on federation links which I would have expected to catch this issue before too long (by closing the connection).
How should I manage this issue?
There are two issues. The first is ensuring that 'broken' connections are detected properly. It sounds like perhaps this is not happening in your case. More detail might help identify why. Are you using firewalls to emulate connectivity failures?
The other issue is more generally handling the fact that you cannot buffer indefinitely, will eventually hit some limit and you want this to be clear and to affect the link rather than publishers to the source.
This could for example be using a ring queue for the route (or when it is available a delete policy https://issues.apache.org/jira/browse/QPID-3247). However at present you can't control the details of the queue for exchange routes. You would need to explicitly create a queue and then use a queue route from that.
--------------------------------------------------------------------- Apache Qpid - AMQP Messaging Implementation Project: http://qpid.apache.org Use/Interact: mailto:[email protected]
