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Cc: current@freebsd.org
Subject: Re: Official request: Please make GNU grep the default
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On 2010-08-17 18:29, Alan Cox wrote:
> Try it again on a memory resident file with the MAP_PREFAULT_READ option
> that is provided by this patch:
> 
> http://www.cs.rice.edu/~alc/MAP_PREFAULT_READ.patch

A time trial gives:

  grep with normal mmap()       1396s
  grep with prefault mmap()     1354s
  grep with regular read()      1354s

So normal mmap is ~3% slower, and prefault mmap does not seem to make
any measurable difference.  I guess the added complexity is not really
worth it, for now.