From: lm@mcvoy.com (Larry McVoy)
Subject: [TUHS] Short history of 'grep'
Date: Sat, 30 Jan 2016 17:50:56 -0800 [thread overview]
Message-ID: <20160131015056.GB14210@mcvoy.com> (raw)
In-Reply-To: <alpine.BSF.2.11.1601311227470.14724@aneurin.horsfall.org>
If you really want to see a fast grep then you need to look at gnu
grep by Mike Haertel. Thread about it here:
http://lists.freebsd.org/pipermail/freebsd-current/2010-August/019310.html
If you are a performance nerd then that thread and that code is worth
a read. Mike is extremely good at performance. He's as good at that
as all the original Unix people were at getting stuff to fit in a small
amount of memory.
I like to think of myself as a performance guy but Mike is better.
On Sun, Jan 31, 2016 at 12:41:15PM +1100, Dave Horsfall wrote:
> I'm still trying to get my around about how a program such as "egrep"
> which handles complex patterns can be faster than one that doesn't... It
> seems to defeat all logic :-)
>
> Is there a simple explanation, involving small words? I've never really
> looked at the theory.
>
> --
> Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."
--
---
Larry McVoy lm at mcvoy.com http://www.mcvoy.com/lm
next prev parent reply other threads:[~2016-01-31 1:50 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-30 3:00 Warren Toomey
2016-01-30 19:10 ` Mary Ann Horton
2016-01-30 19:44 ` Dave Horsfall
2016-01-30 20:20 ` Mary Ann Horton
2016-01-30 20:40 ` Dave Horsfall
2016-01-30 21:42 ` Marc Rochkind
2016-01-31 1:41 ` Dave Horsfall
2016-01-31 1:50 ` Larry McVoy [this message]
2016-01-31 2:06 ` jason-tuhs
2016-01-31 4:20 ` Random832
2016-01-31 17:11 ` Mary Ann Horton
2016-01-31 17:38 ` John Cowan
2016-02-01 10:48 ` Tony Finch
2016-01-31 2:37 ` John Cowan
2016-02-01 10:38 ` Tony Finch
2016-02-01 19:26 ` scj
2016-01-31 17:01 Doug McIlroy
2016-03-05 1:48 ` Dave Horsfall
2016-03-05 1:54 ` Larry McVoy
2016-02-01 20:57 Doug McIlroy
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