in reply to Re: String Concatenation Performance
in thread String Concatenation Performance

When I bump the loops to a million reps I get: 

            (warning: too few iterations for a reliable count)
            (warning: too few iterations for a reliable count)
           Rate nonint interp
  nonint 1.39/s     --    -1%
  interp 1.41/s     1%     --

[download]

Replies are listed 'Best First'.
Re: Re: Re: String Concatenation Performance
by TomDLux (Vicar) on Mar 20, 2004 at 16:57 UTC

    I humbly suggest that you only thought you were getting a million reps. Since the output says you were getting 1.4 reps per second, on average, the two million reps ( nonint + interp ) should take 1428571 seconds, which is over 16 days. So, unless you've invented a time machine, to get the report back to us so quickly ....

    When I say a million reps, I mean replacing the '-1' iteration count with a specific value:

    cmpthese (1_000_000, {interp => "interpolated()",
                      nonint => "noninterpolated()"});

    [download]

    --
    TTTATCGGTCGTTATATAGATGTTTGCA

[reply]
[d/l]

      I bumped my own loop in the subs to 1_000_000, so I got my multiplier, but not the way you did. I figured it didn't matter where the looping occurred, and that if it was inside the sub, then my test would include more concatenation and less call dispatch. The time machine on the other hand, won't compile strict yet.

      I still have this problem, though, in that I don't trust my own results. I believe there to be an inherent hit taken when using $old="$old$new" over $old.=$new because of the necessary runtime scanning. Does anyone have anything to say on that?

[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom