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c++profilingsolaris

Count function calls on Solaris

I'm currently profiling a C++ application on Solaris using collect and analyser, but I only see the number of seconds spent in each functions.

How can I see the number of time each function was called ?

Is there any options I should add to the command line to enable counters? or should I use a different tool ?

Solution

  • The collect command doesn't work that way - it samples the running executable to get the call stack data it collects.

    You need to compile with -xpg and use prof or gprof on the output data file produced.

    Something like this dtrace script would also collect function call counts:

    countfuncs.d:

    pid$target:::entry
{
    @[ probefunc ] = count();
}

    Then run that:

    dtrace -s countfuncs.d -c your_program ...

    In my experience, counting the number of times a function is called doesn't really matter - it's how much time (CPU or wall-clock) is spent in any function that matters. If a function takes up 90% of your execution time, that's where you spend your effort optimizing performance, whether the function was called once or billions of times. If a function takes up 0.001% of execution time, you don't bother with it no matter how many times it gets called.