Is there any standard for comparing runtimes experimentally?
In addition to elapsed time for each run, report seconds of user &amp; system mode, and total IP packets, and total disk I/Os, if only to verify that some numbers are consistently "low" and have negligible impact on elapsed time.

On https://wiki.freebsd.org/BenchmarkAdvice PHK and others offer good advice, including


  Use ministat to see if your numbers are significant. Consider buying "Cartoon guide to statistics"