> Can you provide some scenario, when this is useful? Server Push is an http hack that enables the server to send a message to the client immediately, without the need for a client to poll the server. Basically, the client makes an XMLHTTP request to which the server doesn't answer immediately, but only answers when an event occurs, or when it times out (then the client re-opens the connection).
Examples: 1. Chat rooms. It's nice to post new messages to the clients as soon as they become available. 2. A Mail client can inform the user of new mail as soon as it arrives. (as does gmail) 3. Long searches can return as soon as data is available, without polling the server every n seconds. More details here: http://code.google.com/p/google-web-toolkit-incubator/wiki/ServerPushFAQ Now., the problem is that valuable server resources are taken up by these lingering connections: 1) A TCP Connection. The practical limit on these is ~100,000. Which is pretty high. I could live with that. 2) The Server Thread. The limit is very low, on the order of ~100. That's why it is very important to be able to release the server thread. Hope this helps, - Rustam - -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
