By the undef $/, the file is read in as a huge string. Of course I checked, and with a n=1000 string I get: 
          Rate  regex substr
regex  21775/s     --   -27%
substr 29748/s    37%     --

[download]
Which makes sense, as my file has some 50k chars.

Jeroen
"We are not alone"(FZ)

Update: (I'm not going to make a Re:{9} post)

I'd say, start checking the source {grin} 

$str='a'x1E6; 
=>
         Rate  regex substr
regex  15.1/s     --   -16%
substr 18.0/s    19%     --
$str='a'x1E7;
=>
         Rate  regex substr
regex  1.41/s     --   -21%
substr 1.79/s    27%     --

[download]
At 100M, I'm testing my swap ;-)..... I tried it nevertheless, but now I'm waiting for my box stop swapping... /me is afraid that may take a while... :-)... finally, I had to use that reboot button :-<
25M still went OK: 
       s/iter  regex substr
regex    1.80     --   -21%
substr   1.42    27%     --

[download]
at 50M, benchmark produced a division by zero .....

In reply to Re:{6} how do I line-wrap while copying to stdout? by jeroenes
in thread how do I line-wrap while copying to stdout? by ams

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