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Pattern Matchin Huge File

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# 8  
Old 02-10-2011
What happens when you run these commands in the foreground? There seems to be a discrepancy between real time and user/sys .

I get these times in the foreground:

gawk '{p=substr($0,155,2)} p ~ "3[19]" {print > p ".txt"}' LOAD.txt1m31.08
{ grep '^.\{154\}39' LOAD.txt > 39.txt; grep '^.\{154\}31' LOAD.txt > 31.txt; }0m43.541s
mawk '{p=substr($0,155,2)} p ~ "3[19]" {print > p ".txt"}' LOAD.txt0m9.168s
Last edited by Scrutinizer; 02-10-2011 at 06:59 AM..
# 9  
Old 02-10-2011
It ok with the timings now, Because earlier it took me around an hour but from your command its only minutes.

I love to run the command in backgroud as this wont distrub if i left it.

Also a small request for you. Vould please explain me the command which you used.

Code:
 
grep '^.\{154\}39' LOAD.txt > 39.txt

# 10  
Old 02-10-2011
Hi you can of course run your commands in the background, but to accurately determine the fastest solution the speed tests need to be run in the foreground on a preferrably quiet system (or rather with sufficient priority).

My command means select lines that match 154 characters ( . ) at the beginning of the line ( ^ ), followed by 39
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