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Subject: Re: 1.7] BUG - GREP slows to a crawl with large number of matches 	on  	a single file
From: Richard Foulk <richard AT skydive1 DOT com>
To: cygwin AT cygwin DOT com
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Date: Sat, 07 Nov 2009 12:27:11 -1000
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Jim Reisert wrote:

>On Fri, Nov 6, 2009 at 7:12 AM, Cooper, Karl (US SSA)
><karl DOT cooper AT baesystems DOT com> wrote:
>
>> Corinna Vinschen wrote:
>>> Or try LANG=C.ASCII since LANG=C will still return UTF-8 as charset
>>> when calling nl_langinfo(CHARSET).
>>
>> Yes, this solves it:
>>
>> $ time LC_ALL=C.ASCII grep dog testfile | wc
>>  100000  900000 4500000
>>
>> real    0m0.359s
>> user    0m0.279s
>> sys     0m0.232s
>
>
> I just tried this on my system, I routinely grep groups of files
> containing 100K lines.  I was *astounded* how fast "grep" is after
> setting LC_ALL=C.ASCII !


The second run of grep is usually much faster due to disk buffering.




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