Oh I see, I thought what you meant was that I could only alter the default group in shared-groups mode starting with 0.24. To make sure I'm understanding this correctly -- changing the the default message group name to something else in C++ mode won't change the serial processing behavior I saw, right? Messages without a group identifier will still be considered to be in a group -- rather than no group -- and they cannot be processed by multiple consumers concurrently?
Thanks, Helen On Tue, Jan 7, 2014 at 8:22 PM, Robbie Gemmell <robbie.gemm...@gmail.com>wrote: > I just noticed you said you were using 0.16, somehow glossed over it > originally and only noticed the 0.24 in the doc URL (its many hours past > time I was asleep, I might be getting tired). > > Realising that, I should add that prior to 0.22 the only way to alter the > default group in the shared-groups mode from 'qpid.no-group' to something > else would have been via the 'qpid.default-message-group' queue declare > argument when using an AMQP client to create the queue originally, and for > 0.22 itself only that and the system property approach I mentioned would > work. > > Robbie > > On 8 January 2014 04:03, Helen Kwong <helenkw...@gmail.com> wrote: > > > Hi Robbie, > > > > I see. Thanks for the quick response and explanation! > > > > Helen > > > > > > On Tue, Jan 7, 2014 at 7:43 PM, Robbie Gemmell <robbie.gemm...@gmail.com > > >wrote: > > > > > Hi Helen, > > > > > > The short answer to your question is that it is the documentation which > > is > > > incorrect, and the behaviour you are seeing is expected. > > > > > > The long answer is, when that documentation was composed a segment was > > > missed out indicating this, and needs to be added to the docs. The > > > behaviour listed for when no group is specified is only true of the > > > 'non-shared' groups supported by the Java broker, in the C++/shared > group > > > mode any messages recieved without an explicit group value are all > > assigned > > > to a default group of 'qpid.no-group'. This is as per the behaviour of > > the > > > C++ broker itself, which is explained in the C++ broker docs at the end > > of > > > the following page > > > > > > > > > http://qpid.apache.org/releases/qpid-0.24/cpp-broker/book/Using-message-groups.html > > > . > > > For the 0.24 Java broker, this default shared group can be changed > > > broker-wide using the Java system property > > > 'qpid.broker_default-shared-message-group', or can be overriden for an > > > individual queue during creation programatically via AMQP clients or > the > > > management interfaces through use of the argument > > > 'qpid.default-message-group' or 'messageGroupDefaultGroup'. > > > > > > I coincidentally happened to have fixed a defect with the shared groups > > > functionality last night on trunk. Its not yet included in the imminent > > > 0.26 release, though I am about to request whether that is possible. > > > https://issues.apache.org/jira/browse/QPID-5450 > > > > > > Robbie > > > > > > On 8 January 2014 02:43, Helen Kwong <helenkw...@gmail.com> wrote: > > > > > > > Hi, > > > > > > > > I use the Java broker and client, version 0.16, and am considering > > using > > > > the message grouping feature ( > > > > > > > > > > > > > > http://qpid.apache.org/releases/qpid-0.24/java-broker/book/Java-Broker-Queues.html#Java-Broker-Queues-OtherTypes-Message-Grouping > > > > ). > > > > From testing I've done, there seems to be a bug with the C++ > > > compatibility > > > > model, and I'm wondering if this is a known issue. Specifically, in > my > > > test > > > > I have a queue configured to use a group header field with > > > > "qpid.group_header_key" and C++ mode with "qpid.shared_msg_group", > and > > > have > > > > multiple listeners to the queue. Each listener will sleep for a short > > > > amount of time when it receives a message before returning. I then > > > enqueue > > > > 10 messages that do not have a value in the group header field to the > > > > queue. Since the doc says that messages without a value in the > grouping > > > > header will be delivered to any available consumer, the behavior I > > expect > > > > is that the messages will be processed in parallel, i.e., when > > listener 1 > > > > is holding on to a message and sleeping, listener 2 can receive > another > > > > message from the queue. But what I see is that the messages are > > processed > > > > serially -- message 2 won't be received by some thread until message > 1 > > is > > > > done. When I use the default mode instead of C++ mode, then I get the > > > > parallel processing behavior. > > > > > > > > Is this is a known bug, and is there a fix for it already? > > > > > > > > Thanks, > > > > Helen > > > > > > > > > >
