Sounds good. Does virtual topics will fit ServiceMix requirement for WS-Notification clustering ? Currently, one problem is that if you deploy the same WS-Notification consumer on several nodes, they will not act as a single consumer with load balancing between the consumers. It seems to be the exact need :) I will raise a JIRA so we update the WS-Notification component to use virtual topics, once we upgrade to AMQ 4.1.
Cheers, Guillaume Nodet On 7/27/06, James Strachan <[EMAIL PROTECTED]> wrote:
I've made a few changes to the virtual destinations feature... http://activemq.org/site/virtual-destinations.html Firstly I wanted to have out of the box support for virtual topics; however I was a little worried about adding the extra overhead of virtual topic functionality to everyones installation of ActiveMQ, particularly as some users have very high performance requirements. So I refactored the virtual destination functionality to be a form of DestinationInterceptor. That way the cost is only incurred when sending to a destination which has a virtual destination capability added. It also means we can add per-destination interceptors easily now (I"m sure we could think of some other useful ones in the future). I wanted to make virtual topics available as a default, but not impose the cost of them (even though they are fairly cheap). Also I was having reservations of my previous suggestion of using ActiveMQ.Virtual.> as the prefix for consumers - as ActiveMQ.> is typically the internal administration namespace. So I'm thinking of the following out of the box (you can of course configure this explicitly to do whatever you need via XML or Java code)... Topics matching VirtualTopic.> get the virtual topic capability - other topics do not. (So zero overhead added). To consume from the virtual topic via a queue you subscribe to Consumer.$subscriberName.VirtualTopic.> e.g. you could publsh to topic VirtualTopic.Cheese and subscribe to Consumer.A.VirtualTopic.Cheese using the default to get virtual topics. (Or for another virtual topic consumer just subscribe to Consumer.B.VirtualTopic.Cheese). To enable virtual topics on any topic (incurring a small cost per send) then you could configure something like this which effectively matches all topics <broker> <virtualDestinations> <virtualTopic name=">"/> </virtualDestinations> or you could create custom virtualTopic wildcards if you wish etc. Does this seem OK to folks? -- James ------- http://radio.weblogs.com/0112098/
-- Cheers, Guillaume Nodet
