[calpaterson]

Hi - not sure what you mean by this. The sync workers handle one request (to completion) per worker. So 16 workers means 16 concurrent requests. For the async workers it's different - they do more concurrently - but as discussed their throughput is not better (and latency much worse).

Maybe what you're getting at is cases where there are a large number of (fairly sleepy) open connections? Eg for push updates and other websockety things. I didn't test that I'm afraid. The state of the art there seems to be using async and I think that's a broadly appropriate usage though that is generally not very performance sensitive code except that you try to do as little as possible in your connection manager code.

[fnord123]

In the case of everything working smoothly that model may play out. But if you get a client that times out, or worse, a slow connection then they used one of your workers for a long time in a synchronous model. In the async model this has less of a footprint as you are still accepting other connections despite the slow progress of one of the workers.

[blondin]

yes many open connections is what i meant (suggested by other people as well). by the way, i really liked the writing, it's refreshing. and i agree with you that people aren't using async for the right reasons.

[calpaterson]

Thanks :) , really appreciate that. I think all technology goes through a period of wild over-application early on. My country is full of (hand dug) canals for example