Actually, with this very code I got 15% variation between runs of identical code. I find this is often true when benchmarking nano-optimizations like this. That is why I consider 20% to be "indeterminate" (I add 5% to "be safe") for nano-optimization benchmarks.

Now, for macro-optimization benchmarks, I consider 5% to be "indeterminate". The problem with nano-optimization benchmarks is that the run time of the code being timed is so miniscule per iteration that slight variations in the "outside" code can make a relatively large impact on the timing results.

And, of course, the other problem with nano-optimization is that even if you find a 2-fold speed-up for one of these tiny, tiny operations, the actual change you end up seeing in how long it takes your script to run is usually a tiny fraction of that.

        - tye (but they are fun, aren't they?)

In reply to (tye)Re2: speed of comparisons of things by tye
in thread speed of comparisons of things by John M. Dlugosz

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.