Thanks Jeff,
First of all, thanks for the informative reply. You've no idea how helpful these pointers are for me. In response to your suggestions, I've come up with some ideas of my own. My original architecture resembled Christophe Coenraets' original JMS Portfolio Viewer, but now I'm leaning towards the "improved" Java-only example that you mentioned (Example #6 in the Testdrive). My new plan is to use a single JMS bus to transport messages behind the scenes from my DB machine to my LCDS server. As you suggested I'll have a thread running on the LCDS server that does the JNDI thing and parses the JMS messages from the DB machine and converts them into AsyncMessages to be pushed out to flex clients via LCDS' RTMP. Sounds easy right? The one thing that I don't understand is how to configure tomcat/activeMQ and JNDI to function as it does in the Testdrive Server. The Testdrive just installs without much in the way of an installation guide. Also, the Testdrive Server does not actually demonstrate how to parse JMS messages. The Feed example just has a java thread that publishes AsyncMessages to the "Feed" destination. No JNDI or JMS listener thread. The hardest and most time-consuming part of this is properly configuring LCDS and Tomcat/ActiveMQ as well as the JMS bus. Also, I know that Jrun has a bootstrapping feature that you can use at server startup. I'm not sure if tomcat has a similar feature. (This would be helpful for starting that JMS listener thread). Best, Justin On 8/27/07, Jeff Vroom <[EMAIL PROTECTED]> wrote: > > The RTMP stuff is pretty scalable – you can have thousands of open > connections per CPU easily as long as each connection does not generate > enough activity on the server to use up too much CPU. > > > > The JMS messaging adapter that ships with LC DS is less scalable and is > more tuned right now for the cases you are not using – i.e. where each > flex client subscribes using unique JMS subscription criteria. Right now, > each client subscription causes its own JMS subscription and JMS consumer. > In the case you are subscribing it sounds more like you want to broadcast > messages to all of the flex subscribers. I think for this, you'd really > only want one JMS consumer per server. One thread would pull the message > out of JMS and use the ActionScript messaging adapter to push the message to > the clients. It is easy to do the latter part – there is a simple api call > which the server can use to send a message to all subscribers to a > particular destination. Getting the message out of JMS asynchronously is > also not too difficult but doing anything asynchronous in JEE can cause > portability problems if you are running on an app server like Websphere > which limits your ability to create threads etc. We have solved those > problems using the WorkManager api which is supported by Websphere. > > > > Our thought is to open up some apis to make getting messages out of JMS > pretty easy using these libraries so you would be able to use our code to > create your own JMS consumers as necessary. You could then easily write the > code that converts the JMS message to a flex message and use the > ActionScript adapter to push that message to the subscribed flex clients. > In the meantime, you could use a message driven bean or if you are running > on tomcat or a less strict app server, just fire up your own thread to read > messages out of JMS and use our apis to push messages to subscribed flex > clients. See the "Feed.java" file in the samples directory for an example > which uses those apis. > > > > Jeff > > > ------------------------------ > > *From:* [email protected] [mailto:[EMAIL PROTECTED] *On > Behalf Of *jfujita1 > *Sent:* Wednesday, August 22, 2007 11:18 AM > *To:* [email protected] > *Subject:* [flexcoders] Just how powerful is LCDS' JMS + RTMP? > > > > I've seen the example leveraging LCDS' RTMP protocol coupled with a > JMS back end to broadcast messages to clients, but just how scalable > is this? Suppose I set up a single NON-persistent, NON-durable JMS > topic with 50,000 flex clients subscribed via RTMP. Does anybody have > any experience with this sort of scale? > > Thanks in Advance, > > -Justin > > > -- Thanks for reading. -Justin Flickr: http://www.flickr.com/photos/neopan/
