Message-ID: <4AF393C6.3000505@tlinx.org>
Date: Thu, 05 Nov 2009 19:11:02 -0800
From: Linda Walsh <cygwin@tlinx.org>
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To: cygwin@cygwin.com
Subject: Re: 1.7] BUG - GREP slows to a crawl with large number of matches on a  single file
References: <26224019.post@talk.nabble.com>
In-Reply-To: <26224019.post@talk.nabble.com>
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aputerguy wrote:
> Running grep on a 20MB file with ~100,000 matches takes an incredible almost
> 8 minutes under Cygwin 1.7 while taking just 0.2 seconds under Cygwin 1.5
> (on a 2nd machine).
---
	I've seen nasty behavior with grep that isnt' cygwin 
specific.  Try "pcregrep" and see if you have the same issue.

	I found it to be about ~100 times faster under _some_ searches
though 2-3x is more typical. The gnu re-parser isn't real 
efficient under some circumstances.  

	If you find a big difference, you might also want to report
it to the bug-grep@gnu.org mailing list, but last time I did,
they told me "that's the way it is" due to some posix conformance
thing...

-l

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