Yes, memory usage should be 0 for a destination if there are no messages so this seems like a bug. There was another memory bug fixed more recently but that only had to do with persistent messages when using concurrent store and dispatch. As you pointed out the best thing to do to help would be to create a test case that can reproduce the issue but make sure you use the latest version (5.14.4).
On Wed, Mar 15, 2017 at 7:01 AM, <david.sit...@gmail.com> wrote: > Hi, > > I have an application using ActiveMQ 5.13.5 which uses non-persistent > messages. There is a queue which has several producers and a single > consumer. > > At times I see the CursorMemoryUsage not being 0 despite the queue being > empty. When this application runs for a very long time, > CursorMemoryUsage grows and this can become an issue with system memory > usage. My understanding might be wrong but is this a problem? > > At first this sounded like > https://issues.apache.org/jira/browse/AMQ-6094 but this has apparently > been fixed for this release. > > I've attached a jconsole view showing the issue. When I invoked via JMX > these operations they return: > > doesCursorHaveMessagesBuffered -> false > cursorSize -> 0 > doesCursorHaveSpace -> 0 > > On a different run, I had DEBUG enabled and I've seen these sort of > lines confirming memory usage despite the queue being empty: > > 2017-03-15 21:47:55,624 [ActiveMQ > BrokerService[cb01e0612bb1468d88828716182f7f39] Task-5] 214837 DEBUG > org.apache.activemq.broker.region.Queue - queue://master-items-7.0, > subscriptions=1, memory=0%, size=0, pending=0 toPageIn: 0, Inflight: 0, > pagedInMessages.size 0, pagedInPendingDispatch.size 0, enqueueCount: > 5518, dequeueCount: 5518, memUsage:28538 > > Is this a bug? I know I'll be asked for a test case, but I wanted to > confirm it first before proceeding. > > > > -- > Cheers, > David > >
