Hello all
On Thu, 18 Jan 2007, James.Strachan wrote:
Have you tried setting the UsageManager configuration to something
large? Out
of the box its set to something really tiny.
BTW if you have an issue, please mention the version of the
software you are
using.
http://incubator.apache.org/activemq/support.html
James
Some more details from the day's debugging.
We're running ActiveMQ 4.2 from trunk as checked out on Friday.
Our test has a thread that produces messages. On another connection in
the same application, we have a consumer with a message listener set.
This listener produces a new message.
Debugging with Eclipse, I see that the first time the code goes into
UsageManager.waitForSpace, it is calling from the thread that
produces.
The stack looks like this:
Thread [myapp$MyThread] (Suspended (breakpoint at line 91 in
UsageManager))
UsageManager.waitForSpace() line: 91
UsageManager.waitForSpace() line: 88
Topic.send(ConnectionContext, Message) line: 248
ManagedTopicRegion(AbstractRegion).send(ConnectionContext,
Message) line: 305
ManagedRegionBroker(RegionBroker).send(ConnectionContext, Message)
line: 381
TransactionBroker.send(ConnectionContext, Message) line: 197
AdvisoryBroker(BrokerFilter).send(ConnectionContext, Message)
line: 126
CompositeDestinationBroker.send(ConnectionContext, Message) line: 98
BrokerService$2(MutableBrokerFilter).send(ConnectionContext,
Message) line: 136
TransportConnection.processMessage(Message) line: 449
ActiveMQBytesMessage(ActiveMQMessage).visit(CommandVisitor) line:
604
TransportConnection.service(Command) line: 258
TransportConnection$1.onCommand(Object) line: 164
ResponseCorrelator.onCommand(Object) line: 95
MutexTransport(TransportFilter).onCommand(Object) line: 65
VMTransportServer$1(VMTransport).syncOneWay(Object) line: 99
VMTransportServer$1(VMTransport).oneway(Object) line: 86
MutexTransport.oneway(Object) line: 44
ResponseCorrelator.asyncRequest(Object, ResponseCallback) line: 69
ResponseCorrelator.request(Object) line: 74
ActiveMQConnection.syncSendPacket(Command) line: 1185
ActiveMQSession.send(ActiveMQMessageProducer, ActiveMQDestination,
Message, int, int, long) line: 1547
ActiveMQMessageProducer.send(Destination, Message, int, int, long)
line: 473
ActiveMQMessageProducer.send(Message) line: 358
<thread in my application calling send>
If I then allow the VM to continue, it runs for a short while and then
the single remaining ActiveMQ Session Task thread blocks:
Thread [ActiveMQ Session Task] (Suspended (breakpoint at line 91 in
UsageManager))
UsageManager.waitForSpace() line: 91
UsageManager.waitForSpace() line: 88
Topic.send(ConnectionContext, Message) line: 248
ManagedTopicRegion(AbstractRegion).send(ConnectionContext,
Message) line: 305
ManagedRegionBroker(RegionBroker).send(ConnectionContext, Message)
line: 381
TransactionBroker.send(ConnectionContext, Message) line: 197
AdvisoryBroker(BrokerFilter).send(ConnectionContext, Message)
line: 126
CompositeDestinationBroker.send(ConnectionContext, Message) line: 98
BrokerService$2(MutableBrokerFilter).send(ConnectionContext,
Message) line: 136
TransportConnection.processMessage(Message) line: 449
ActiveMQBytesMessage(ActiveMQMessage).visit(CommandVisitor) line:
604
TransportConnection.service(Command) line: 258
TransportConnection$1.onCommand(Object) line: 164
ResponseCorrelator.onCommand(Object) line: 95
MutexTransport(TransportFilter).onCommand(Object) line: 65
VMTransportServer$1(VMTransport).syncOneWay(Object) line: 99
VMTransportServer$1(VMTransport).oneway(Object) line: 86
MutexTransport.oneway(Object) line: 44
ResponseCorrelator.asyncRequest(Object, ResponseCallback) line: 69
ResponseCorrelator.request(Object) line: 74
ActiveMQConnection.syncSendPacket(Command) line: 1185
ActiveMQSession.send(ActiveMQMessageProducer, ActiveMQDestination,
Message, int, int, long) line: 1547
ActiveMQMessageProducer.send(Destination, Message, int, int, long)
line: 473
ActiveMQMessageProducer.send(Message) line: 358
<onMessage of listener in my application is called. it calls send.>
ActiveMQMessageConsumer.dispatch(MessageDispatch) line: 870
ActiveMQSessionExecutor.dispatch(MessageDispatch) line: 99
ActiveMQSessionExecutor.iterate() line: 166
PooledTaskRunner.runTask() line: 111
PooledTaskRunner.access$1(PooledTaskRunner) line: 95
PooledTaskRunner$1.run() line: 44
ThreadPoolExecutor$Worker.runTask(Runnable) line: 885
ThreadPoolExecutor$Worker.run() line: 907
Thread.run() line: 619
There doesn't seem to be any other ActiveMQ threads around, so I can't
see how this thread is going to wake up from its
usageMutex.wait();
that is blocking on.
Any thoughts? Is it wrong to produce straight from a message listener?
By the way, I noticed that increasing the memory available to the
memory manager from 20 MB to 128 MB actually makes the application
block
sooner rather than later. I also experimented with some prefetch
policy
settings, but these don't make much of a difference. Currently, we're
simply using
vm://localhost?broker.useJmx=true&broker.persistent=false
as our broker URL.
We're using topics throughout. Sessions' acknowledge modes are all set
to DUPS_OK_ACKNOWLEDGE. We're doing some message selection with string
and integer properties.
Cheers,
Albert
