What are the advantages and disadvantages of Liftweb Comet?

What are the advantages and disadvantages of Liftweb Comet over other HTTP Server push technologies? - How scalable is lif开发者_如何学Pythontweb comet? - design issues and dependencies etc..,

Comet is a generic term for Ajax HTTP server push. See this link for more details:

http://exploring.liftweb.net/master/index-11.html

I believe this is the only way to implement server push with Lift.

The advantage of using Comet over Ajax polling are well described in the link above (reduced traffic/better responsiveness).

According to this source Lift Comet is most scalable on Jetty due to the use of non-blocking IO, but it seems to be a controversial topic:

Comet VS Ajax polling

Java I/O vs. Java new I/O (NIO) with Linux NPTL

If you gave more details on the alternatives to Comet you consider it would be easier to give you the relative advantages and disadvantages.