Using JConsole or another JMX viewer gives you really valuable insight into the status of the subscriptions (by both clients and brokers) and can help you figure out where messages are going unconsumed.
I wouldn't bother with unit tests for this; just set up a test environment with two brokers plus a consumer on one and a producer on the other, and have the producer publish messages as fast as it can, and then pause the consumer (e.g. by attaching a debugger and pausing all threads). Tim On Sep 17, 2015 10:29 AM, "bbuzzard" <[email protected]> wrote: > Tim, > I'm using ActiveMQ-5.5.1 (yes I know there are newer > versions, but we're not ready to upgrade our production code just yet. We > have a star topology with multiple end point brokers feeding a central > broker (hub) that controls routing of messages from end point to end point. > > e.g. Broker A (end point) --> Broker (hub) --> Broker B (end point) > --> Broker (hub) --> Broker C > (All end point brokers send their messages to the same > queue on the hub called "hub") > > Here's the problem I'm having. Files from Broker A go through the hub on > their way to Broker B. Broker B captures information from the files and > sends the files back to the hub where they can be routed to Broker C. Most > of the time the memory usage stays below 10%, but once and a while it > climbs up very rapidly 25%, 50%, 75% and then all logging stops in Broker B > and file transfers between the hub and Broker B appear to stop until I > restart Broker B. If I had to guess I would say that the high water mark > is reached in the hub (since it's receiving files from other brokers not > shown above) and it halts the Producer Flow from Broker B, but I'm not > seeing anything that indicates the flow can be resumed. > > Can you suggest some ways to isolate this problem? I was thinking of > using the existing Producer Flow Control test and modifying the test to > match my topology, but that might take a little time for me to come up to > speed on. > > From: Tim Bain [via ActiveMQ] [mailto: > [email protected]] > Sent: Thursday, September 17, 2015 9:04 AM > To: Billy Buzzard > Subject: RE: Does Publisher Flow Control work across a Network Bridge? > > I've observed it in practice, so I've never felt the need to search for a > unit test that shows the same thing, sorry. Luckily they're all open > source, so you can do that yourself if you're so inclined. > On Sep 17, 2015 7:09 AM, "bbuzzard" <[hidden > email]</user/SendEmail.jtp?type=node&node=4702062&i=0>> wrote: > > > I assumed it worked that way, but I wasn't sure. Thank you. > > > > Is there a specific Test Case that proves this? > > > > From: Tim Bain [via ActiveMQ] [mailto: > > [hidden email]</user/SendEmail.jtp?type=node&node=4702062&i=1>] > > Sent: Wednesday, September 16, 2015 11:04 PM > > To: Billy Buzzard > > Subject: Re: Does Publisher Flow Control work across a Network Bridge? > > > > In that situation, broker 2 will PFC broker 1, and then (later, once > broker > > 1 hits a usage limit) broker 1 will PFC the producer. > > > > In a NoB, each broker acts as a producer or a consumer on each > > networkConnector, so the brokers experience the same interactions that > > clients do, and any interaction between two clients (sending a message, > > PFC, etc.) happens because that interaction has happened repeatedly > across > > each network link where the brokers play the roles of producer and/or > > consumer. > > On Sep 16, 2015 12:03 PM, "bbuzzard" <[hidden > > email]</user/SendEmail.jtp?type=node&node=4702052&i=0>> > > wrote: > > > > > I have two brokers, each on its own machine, connected together via a > > > Network > > > Bridge where one end uses a full duplex connection. I'm sending in > > > messages > > > to the queue shared by both machines at a high rate and I'm expecting > > > Publisher Flow control to kick in and not let me publish anymore > messages > > > until the consumer on the other machine clears out some messages. > > > > > > Does Publisher Flow Control work across two machines using a Network > > Bridge > > > or is it limited to a single machine? > > > > > > > > > > > > -- > > > View this message in context: > > > > > > http://activemq.2283324.n4.nabble.com/Does-Publisher-Flow-Control-work-across-a-Network-Bridge-tp4702039.html > > > Sent from the ActiveMQ - User mailing list archive at Nabble.com. > > > > > > > ________________________________ > > If you reply to this email, your message will be added to the discussion > > below: > > > > > http://activemq.2283324.n4.nabble.com/Does-Publisher-Flow-Control-work-across-a-Network-Bridge-tp4702039p4702052.html > > To unsubscribe from Does Publisher Flow Control work across a Network > > Bridge?, click here< > > >. > > NAML< > > > http://activemq.2283324.n4.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml > > > > > > > > > > > > > -- > > View this message in context: > > > http://activemq.2283324.n4.nabble.com/Does-Publisher-Flow-Control-work-across-a-Network-Bridge-tp4702039p4702058.html > > Sent from the ActiveMQ - User mailing list archive at Nabble.com. > > ________________________________ > If you reply to this email, your message will be added to the discussion > below: > > http://activemq.2283324.n4.nabble.com/Does-Publisher-Flow-Control-work-across-a-Network-Bridge-tp4702039p4702062.html > To unsubscribe from Does Publisher Flow Control work across a Network > Bridge?, click here< > http://activemq.2283324.n4.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=4702039&code=QmlsbHkuQnV6emFyZEBibnNmbG9naXN0aWNzLmNvbXw0NzAyMDM5fC05MjA3NTk2MzE= > >. > NAML< > http://activemq.2283324.n4.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml > > > > > > > -- > View this message in context: > http://activemq.2283324.n4.nabble.com/Does-Publisher-Flow-Control-work-across-a-Network-Bridge-tp4702039p4702064.html > Sent from the ActiveMQ - User mailing list archive at Nabble.com.
