<br>We wrote a plugin to Perlbal to handle exactly this case. The plugin waches a flag stored in memcached. When the flag indicates there is new data, the plugin either releases the connection to proxy back to our app server (PHP for us) or immediately returns a result to the client based on the memcached data. We've seen tremendous performance improvements with this approach - we've cut the number of machines required to host the chat part of our application by about a factor of 5.
<br><br>Our plugin code is specific to our protocol, but would be a decent example from which to write a plugin for your case. The async memcached client has been in production without significant issues for 6 months and would be completely reusable to other applications.
<br><br>I've been meaning to publish this code (along with our new Mogile plugin for perlbal). I'll do this today and post again to the list with a link.<br><br>Chris<br><br><div><span class="gmail_quote">On 8/2/06, <b class="gmail_sendername">
Abhishek Pokharna</b> <<a href="mailto:pokharnaabhishek@yahoo.co.in">pokharnaabhishek@yahoo.co.in</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div><div>Hi,</div> <div>Our protocol is based on XML over HTTP. Clients polls the servers(we are using JBoss servers) to check if there is some new data.</div> <div> </div> <div>Is there a way by which we can use perlbal to hold the HTTP connection untill there is some data to be sent to the client?
</div> <div> </div> <div>Thanks</div></div><div><span class="sg"> <div>Abhishek</div></span></div><div><span class="ad"><p>
        
        
                </p><hr size="1">
Here's a new way to find what you're looking for - <a href="http://us.rd.yahoo.com/mail/in/yanswers/*http://in.answers.yahoo.com/" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">Yahoo! Answers</a>
<p></p></span></div></blockquote></div><br><br clear="all"><br>-- <br><a href="http://avatars.imvu.com/chris">http://avatars.imvu.com/chris</a>