egrep is very slow : How to improve performance

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# 8  
Old 02-12-2008
Originally Posted by hidnana
I have uploaded the $key as a screenshot as I don't have the text version right now..., it's a big string concatenated by "|".
I had a feeling it was a bloaded regular expression, a regex optimizer is what you need.

You are giving egrep (which is a grep -E dedicated) a pile of 'check for this or this or this or this'. The form you have it in is quite unwieldy. If that could be reduced to this ...


If your not keen on the regular expression thing you can use a program like regex buddy to load your data in (or a dozen mb or so) and then test it.


and get a sense of the regex back (this is from mkregexp from just the above).


My guess is that you want to do something else, but for what your doing a 30seconds isn't that bad for huge files.
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