java - Typical Requests/Second a "server" can handle? -

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i want implement ajax client polling server. leads millions of small requests...

do have rough estimates (based on hardware , experiences, currenlty not have dedicated server hardware yet), how man requets sever can handle example tomcat 7 standard server hardware (8gb ram, 4 cores, 2,5ghz each)? internal processing of 1 request estemated finish within 50 millisecons (only data put ram cache, counters incrementd, light textprocessing , data read memory again return client. fit in ram).

i thankfull experiences made how requests think or able handle on server in comparable environment.

thanks!! jens

50ms gives quite lot of processing, actually... if of these requests polling, presumably changes. how did come estimate? keep 4 cores busy 80 requests per second, of course... that's not awful lot, , wouldn't want run servers @ full capacity whole time, , there'll some overhead simple handling of networking.

to honest, estimates relatively pointless compared trying it. you'll need load test servers anyway, best rather later.

note alternative frequent polling have long "hanging" requests, aka comet. each request held unfulfilled period (e.g. 5-10 minutes) , had change, you'd respond appropriately. way can drastically reduce number of requests - make code harder write (as has asynchronous; don't want 1 thread per request @ point).


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