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>time perl -ne '$s=<>;<>;<>; chomp $s; print "$s\n";' < A_1_1.fq | wc -l
26814958

real 52m27.757s
user 1m11.780s
sys 0m29.310s

>time cat A_1_1.fq | perl -ne '$s=<>;<>;<>; chomp $s; print "$s\n";' | wc -l
26814958

real 0m59.659s
user 0m36.582s
sys 0m4.108s

The files are 26814958 x 4 lines long.

These are the commands that I used and the time statistics. Clearly a massive difference. Not really sure why. This is perl, v5.10.0 built for x86_64-linux-thread-multi

If you've any suggestions for me to check out on the system that I'm using let me know. This is the OS: SUSE Enterprise Linux SP2 64bit


In reply to Re^4: command line perl reading from STDIN by perlhappy
in thread command line perl reading from STDIN by perlhappy

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