I have to agree with lidden, your benchmark is flawed.

  1. The signal to noise ratio between the code being benchmarked and the code being tested is is so low as to obscure the real differences. subroutine calls are very expensive relative to the operations.
  2. Both your tests are used in a void context and are possibly being optimised away.

If you put the tests into a boolean context, and loop the tests to negate the overhead of calling the subs, you consistantly get the boolean operation coming out faster than the modulo operation. Even for modest loop counts:

Perl> $loop = 1; $counter = 0; cmpthese -1, { and=>sub{ for(1..$loop){ ++$counter & 1 and 1 } }, mod=>sub{ for(1..$loop){ ++$counter % 2 and 1 } } };; Rate mod and mod 517876/s -- -2% and 525790/s 2% -- Perl> $loop = 10; $counter = 0; cmpthese -1, { and=>sub{ for(1..$loop){ ++$counter & 1 and 1 } }, mod=>sub{ for(1..$loop){ ++$counter % 2 and 1 } } };; Rate mod and mod 229555/s -- -7% and 245513/s 7% -- Perl> $loop = 100; $counter = 0; cmpthese -1, { and=>sub{ for(1..$loop){ ++$counter & 1 and 1 } }, mod=>sub{ for(1..$loop){ ++$counter % 2 and 1 } } };; Rate mod and mod 35041/s -- -6% and 37118/s 6% -- Perl> $loop = 1000; $counter = 0; cmpthese -1, { and=>sub{ for(1..$loop){ ++$counter & 1 and 1 } }, mod=>sub{ for(1..$loop){ ++$counter % 2 and 1 } } };; Rate mod and mod 3641/s -- -7% and 3931/s 8% -- Perl> $loop = 1000; $counter = 0; cmpthese -1, { and=>sub{ for(1..$loop){ ++$counter & 1 and 1 } }, mod=>sub{ for(1..$loop){ ++$counter % 2 and 1 } } };; Rate mod and mod 3725/s -- -7% and 3989/s 7% --

It's not huge, but it is consistant.


Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: &1 is no faster than %2 when checking for oddness. (Careful what you benchmark) by BrowserUk
in thread &1 is no faster than %2 when checking for oddness. Oh well. by diotalevi

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