Thread: How to find O of threads ?

  1. #1
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    How to find O of threads ?

    Howdy , ...

    I guess this is really lame question for this forum (it must by to obvieus since i even didn't found this in the FAQ ) .

    Any way ...

    When working with threads (mostly in Java but some times with pthreads) i noticed that same thread can take diffrent time (on idle machine ) and when there are n threads this dosn't mean that it will take n * k {k in setZ+) but more as n * p^k .

    I tried to find a quick answer and found the next :
    Head of the software eng. department :
    The best way to find why is to read the Native code behind the OS that implement this (This is the nicest RTFM i got in my life ) .

    2'rd year software development student from Technion :
    Perheps there is a logaritmic or expentional function for some n but then it become liner so to test it you should use really large quantetis.

    Since both answers didn't sutisfy me i come here ...

    so how can i calculate and find the assymtotic function for a given set of threads .
    since even if each thread is O(1) the can take diffrent times.

    I'm searching for some thing as :
    T(n) = h(thread) + O(something)
    why Gaos didn't had a wife ?
    http://bsh83.blogspot.com

  2. #2
    Algorithm Dissector iMalc's Avatar
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    None of that is making any sense.
    Forget trying to get mathematical and just come out and ask a basic one line English question.
    My homepage
    Advice: Take only as directed - If symptoms persist, please see your debugger

    Linus Torvalds: "But it clearly is the only right way. The fact that everybody else does it some other way only means that they are wrong"

  3. #3
    Registered User slingerland3g's Avatar
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  4. #4
    Crazy Fool Perspective's Avatar
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    An assymptotic bound isn't going to explain the difference in run times for a particular implementation. It could be any number of things, from waiting on shared resources to initialization, to race conditions in your program.

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