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Long (1 minute +) KeepAlives GOOD for JSON / Ajax WebService?

I know keepalives are great for eliminating the penalty for a TCP connection when we have a lot of fast sequence requests from a client browser, but what about the case with something like a JSONP web service? This has different characteristics than loading a web page:

  • A client (browser) usually executes 1 request at a time. Not enough for any auxiliary quick access requests for files with links, for example, in HTML.

  • Requests will sometimes be executed sequentially, but most often a few seconds or even minutes from each other. The keepalive setting is very low, as many tips are not always a smart setting. The current default value for Apache is 5 seconds ( http://httpd.apache.org/docs/2.4/mod/core.html#keepalivetimeout ), which is below 1.3 15 seconds ( http://httpd.apache.org /docs/1.3/mod/core.html#keepalivetimeout ). Both of them are much lower than a minute. This may be due to the fact that 15 were too high, or broadband softened latency - or both. The current 5s will probably not bring anything good for this scenario.

We can assume that we do not run a Linux task for each connection - a thread or a process - while the socket remains open in standby mode / WAIT / is blocked by keepalive, but would it be nice to just leave the sockets, which hangs out for several minutes? Possible options are: Nginx, Apache Event MPM, etc., which use the basic functions based on events in nix, for example, kqueue or epoll. Suppose that dynamic content runs in a different task pool and after its completion the keepalive'd socket will be just an open file descriptor.

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Source: https://habr.com/ru/post/1536717/

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