First of all, I want to send my gratitude to the people who developed Twisted. ^_^<br><br>We have this XMPP server that is implemented using twisted (using the epoll reactor). I was tasked to know how many simultaneous connections it can handle. So I wrote an XMPP benchmark tool using twisted that spawns multiple clients. When we used the benchmark tool on two PCs (each spawning 20,000 XMPP clients), the number of successful connect/authorize varies between 37,000~39,000. Adding more clients we get the, "Connection Closed cleanly" error on the XMPP server. Spawning two XMPP servers didn't help to increase the simultaneous connections.
<br><br>Did we hit the ceiling? Or is there anyway we can increase this further? We already configured the ulimit parameters and tinkered with some kernel configurations.<br>