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in reply to Re^2: code optimization
in thread code optimization

Profilers can lead to false optimizations because your measuring the overhead of recording the timings (OS interrupts/OS calls/context switches/mutex hits/evals/method resolution) or 1 run if the func is below the OS timer resolution. I took nytprof to these subs and nytprof changed which is the fastest sub which is no good.

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Re^4: code optimization
by Anonymous Monk on Nov 05, 2011 at 00:13 UTC

    Profilers can lead to false optimizations because your measuring the overhead of recording the timings (OS interrupts/OS calls/context switches/mutex hits/evals/method resolution) or 1 run if the func is below the OS timer resolution. I took nytprof to these subs and nytprof changed which is the fastest sub which is no good.

    Well, Benchmark isn't exactly a profiler, and reinventing Benchmark seems like a particularly pedestrian thing to reinvent, and the overhead is accounted for

    But, regarding NYTProf, I don't get the argument, its not as if it is Benchmark :)