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POC++ timing method with lower sys time
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copied!<p>I'm trying to make my program self timed and I know two methods</p> <p>1) using getrusage</p> <pre><code>truct rusage startu; struct rusage endu; getrusage(RUSAGE_SELF, &startu); //Do computation here getrusage(RUSAGE_SELF, &endu); double start_sec = start.ru_utime.tv_sec + startu.ru_utime.tv_usec/1000000.0; double end_sec = endu.ru_utime.tv_sec + endu.ru_utime.tv_usec/1000000.0; double duration = end_sec - start_sec; </code></pre> <p>This fetches the user time of a program segment.</p> <p>2) using clock(), which gets the processor's executing time</p> <pre><code>double start_sec = (double)clock()/CLOCKS_PER_SEC; //Do computation here double end_sec = (double)clock()/CLOCKS_PER_SEC; double duration = end_sec - start_sec; </code></pre> <p>This fetches the real time of a program segment.</p> <p>However, I get really long sys time for both methods. The user time is also longer than without these timings. System time sometimes even doubles the user time.</p> <p>For example, I'm doing Traveling Salesman Problem, for a input that runs around 3 seconds for both user and real time normally, these two timings both make the user time to be over 5 seconds and real time over 15 secs, which means sys time is around 10 seconds long.</p> <p>I hope to know if there are ways of improvements or other libraries that are capable of shortening the sys time and user time if possible. If I have to user other libraries, I want libraries for both user time timing and real time timing.</p> <p>Thanks for any advice!</p>

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