Re^4: How to optimize a regex on a large file read line by line ?

$ time ./script.pl dict.txt 
Num. Line : 185866729 - Occ : 14900

real    0m39.453s
user    0m38.999s
sys    0m0.445s



$ perl -v

This is perl 5, version 16, subversion 2 (v5.16.2) built for darwin-th
+read-multi-2level
(with 3 registered patches, see perl -V for more detail)
[download]

Mac OS X 10.9.5, Intel Core i7 2.4 GHz, 16 GB RAM 1600 MHz DDR3

You can shove some time off getting rid of $counter and using $. instead, a quick test took about 6 seconds less in my configuration.

perl -ple'$_=reverse' <<<ti.xittelop@oivalf

Io ho capito... ma tu che hai detto?

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Re^5: How to optimize a regex on a large file read line by line ? by John FENDER (Acolyte) on Apr 16, 2016 at 18:03 UTC
So maybe an issue related to my Windows/Distro, i will try to search why. Thanks.	[reply]
Re^6: How to optimize a regex on a large file read line by line ? by polettix (Vicar) on Apr 16, 2016 at 20:53 UTC
You're welcome. I forgot to add that my hard drive is SSD, although this would NOT account for 11 minutes difference. Update added missing negation, thanks ww perl -ple'$_=reverse' <<<ti.xittelop@oivalf Io ho capito... ma tu che hai detto?	[reply]
Re^7: How to optimize a regex on a large file read line by line ? by John FENDER (Acolyte) on Apr 16, 2016 at 21:52 UTC
It make a big difference !!! Regarding the other performance i get from other language, i was expected something between 50 and 100 s. My hard drive is a 2.5 laptop disk with 5200 tpm. The ultra optimized grep.exe give me a very good result of 10s, it's the best time i can get. But before i was going to check huge volumes, perl was fast. For the 195 mb file, i got 0,61s for grep, 2,25 for java/C#, 3,36 for php, 7 for C++ and 2,47 for perl.	[reply]


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