Hot answers tagged sockets
Socket.IO uses WebSocket protocol so you need to look for a load testing tool capable of WebSocket testing. As far as I'm aware there is a WebSocket Plugin for Apache JMeter which can be used to stress your chat application. See WebSocket Testing With Apache JMeter guide for more details.
You could look at Ixia and/or Shunra. Neither are particularly cheap, but both are certainly capable of this. A Linux box would also work for such a situation. If you're after a free packet generator, you could try Ostinato - comes with a GUI as well :)
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