Friday Nov 22, 2013

Optimized WebSocket broadcast

"When you have to make a choice and don't make it, that is in itself a choice."  (William James)  Tyrus logo

The Java API for WebSocket (JSR 356) is one of the API added to Java EE 7. It is a '1.0' release, that means that the API is complete and fully functional. It is often said that premature optimisation is the root of all evil, so an initial implementation can easily be optimised. The same is also true for features, choices had to made as it is impossible to implement all the desired features in an initial release. Clearly, they are different aspects that could easily be improved going forward.

Tyrus serves as the JSR 356 Reference Implementation, it is also a test-bed for potential new WebSocket features and improvements. As always, a proprietary feature of an implementation doesn't necessarily means that this particular feature will be included in a future revision of the specification. It could just remains a proprietary feature or an implementation specific optimisation.

In this post, Pavel Bucek, a Tyrus team member, discuss how a WebSocket Server Endpoint could be improved when it needs to broadcast a message to its connected remote endpoints. In Tyrus 1.3, a new broadcast() method has been introduced, it allows to broadcast a message by re-using the same data frame for all the remote endpoints, by doing so the overall performance should be improved.