Re: Persistent message and selectors

For Queues, that's right - all messages are stored until consumed (once and only once consumption). For Topics, it's a little more complicated. It's easiest to think of it this way: topics never store messages themselves; topic subscriptions may store messages. Durable subscriptions do store mes

Re: high GC activity yields a high percentage of dead letter queue messages.

There could be another issue, but as long as the GC issue persists, it will make tracking down any other problem very challenging. Attacking that first seems like the best approach. -- View this message in context: http://activemq.2283324.n4.nabble.com/high-GC-activity-yields-a-high-percentage

Re: Replicated LevelDB cluster: failed to page in queue messages

Any update on this issue? https://issues.apache.org/jira/browse/AMQ-5459 Regards, Pankaj. On Mon, Dec 1, 2014 at 6:16 PM, pankajtakawale wrote: > Hi, > > I faced following exception while testing ActiveMQ leveldb cluster. > On this exception, master demotes itself to slave. New master faces sam

Re: Selector and Virtual Topic

Selectors will make dispatching slightly slow*er*, but will it make it *slow*? That depends on your setup, and no one but you will be able to answer performance questions about your usecase, your configuration, and your hardware. Try it and see; that's the only way you're going to know whether yo

Re: Persistent message and selectors

For queues, all messages will be stored, irrespective of whether there is currently a consumer for them. That's how queues work. For topics, I expect that the message would be discarded (topic messages are delivered to all applicable subscribers, of which there are zero in this case), but I don't

Re: Is JDBC still used?

James, To the point you made about whether LevelDB is production-ready, I think the consensus from recent threads on this mailing list is that LevelDB in 5.10 (and also 5.11 snapshots, I think) still has more problems than most of the people who've used it are comfortable with. Those bugs will ge

Re: jdbcPersistenceAdapter & dataDirectory

it is redundant when a datasource is specified. If there is no datasource, it will use an embedded derby instance in the data directory. On 6 January 2015 at 09:54, James Green wrote: > Is > http://activemq.apache.org/maven/apidocs/org/apache/activemq/store/jdbc/JDBCPersistenceAdapter.html#setDir

Re: Is JDBC still used?

JDBC Isn’t replicated, it picks the first master as the one that locks the DB , but offers you another way of scaling (albeit slower) the security  of message persistence to say a commercial RDBMS or open source cluster. It is also allows you to do master slave without a “san” - something many

jdbcPersistenceAdapter & dataDirectory

Is http://activemq.apache.org/maven/apidocs/org/apache/activemq/store/jdbc/JDBCPersistenceAdapter.html#setDirectory(java.io.File) not redundant? Looking at http://activemq.apache.org/jdbc-master-slave.html the example configures a JDBC persistence adapter with both a data directory and a data sour

Is JDBC still used?

Looking at http://activemq.apache.org/persistence.html and wondering about building a cluster of brokers for high availability. Seems JDBC was implemented quite some time ago and has been eclipsed by KahaDB and now LevelDB but these are local only. There's something very shiny and new about LevelD

Selector and Virtual Topic

Lets say I have topic: VirtualTopic.A and a Queue Consumer.B.VirtualTopic.A, There are two consumer one subscribing to topic VirtualTopic.A and other on queue Consumer.B.VirtualTopic.A both are using selector? Will there be any problem because of using selectors? Will selector make dispatching fro