From: Linus Torvalds <torvalds@linux-foundation.org>
To: Fredrik Kuivinen <frekui@gmail.com>
Cc: Junio C Hamano <gitster@pobox.com>, Miles Bader <miles@gnu.org>,
Jeff King <peff@peff.net>,
Nguyen Thai Ngoc Duy <pclouds@gmail.com>,
git@vger.kernel.org
Subject: Re: [PATCH] grep: do not do external grep on skip-worktree entries
Date: Mon, 11 Jan 2010 11:29:01 -0800 (PST) [thread overview]
Message-ID: <alpine.LFD.2.00.1001111124480.17145@localhost.localdomain> (raw)
In-Reply-To: <4c8ef71001111119p253170f8q37bcd3708d894a62@mail.gmail.com>
On Mon, 11 Jan 2010, Fredrik Kuivinen wrote:
>
> Any ideas on how this can be explained?
Could it be a bad 'strstr()' implementation?
Try a complex pattern ("qwerty.*as" finds the same line), and see if that
too is slower than before. If that is faster than it used to be (with
--no-ext-grep, of course), then it's strstr() that is badly implemented.
For me, on x86-64 (Fedora-12), strstr() seems to do pretty well. But it's
easy to do a stupid implementation of strstr that does a 'strlen()' first,
for example, and thus always traverses all data _twice_ etc. Depending on
cache sizes etc, that can end up killing performance (or not mattering
much at all..)
Linus
next prev parent reply other threads:[~2010-01-11 19:29 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-12-30 14:11 [PATCH] grep: do not do external grep on skip-worktree entries Nguyễn Thái Ngọc Duy
2009-12-31 7:01 ` Junio C Hamano
2009-12-31 7:09 ` Junio C Hamano
2010-01-02 11:50 ` Nguyen Thai Ngoc Duy
2010-01-02 18:44 ` Junio C Hamano
2010-01-02 19:15 ` Nguyen Thai Ngoc Duy
2010-01-02 19:45 ` Junio C Hamano
2010-01-03 2:35 ` Miles Bader
2010-01-03 2:47 ` Miles Bader
2010-01-03 3:08 ` Miles Bader
2010-01-03 19:32 ` Linus Torvalds
2010-01-03 20:49 ` Junio C Hamano
2010-01-04 5:31 ` Jeff King
2010-01-04 5:52 ` Junio C Hamano
2010-01-04 6:44 ` Jeff King
2010-01-04 7:08 ` Junio C Hamano
2010-01-04 7:14 ` Junio C Hamano
2010-01-04 7:29 ` Jeff King
2010-01-04 7:26 ` Jeff King
2010-01-04 8:09 ` Jeff King
2010-01-04 16:01 ` Linus Torvalds
2010-01-04 15:54 ` Linus Torvalds
2010-01-04 15:57 ` Miles Bader
2010-01-04 16:03 ` Linus Torvalds
2010-01-11 6:39 ` Junio C Hamano
2010-01-11 15:43 ` Linus Torvalds
2010-01-11 15:59 ` Linus Torvalds
2010-01-11 16:22 ` Junio C Hamano
2010-01-11 16:24 ` Junio C Hamano
2010-01-11 16:33 ` Linus Torvalds
2010-01-12 8:29 ` Junio C Hamano
2010-01-12 8:31 ` [PATCH] grep: lookahead optimization can be used with -L option Junio C Hamano
2010-01-12 8:32 ` [PATCH] grep: -L should show empty files Junio C Hamano
2010-01-12 21:27 ` Sverre Rabbelier
2010-01-13 6:56 ` Junio C Hamano
2010-01-13 16:04 ` Sverre Rabbelier
2010-01-13 19:48 ` Junio C Hamano
2010-01-13 6:48 ` [PATCH 1/2] grep: rip out support for external grep Junio C Hamano
2010-01-13 8:29 ` Jay Soffian
2010-01-13 8:59 ` Junio C Hamano
2010-01-13 15:20 ` Linus Torvalds
2010-01-13 6:51 ` [PATCH 2/2] grep: rip out pessimization to use fixmatch() Junio C Hamano
2010-01-12 16:21 ` [PATCH] grep: do not do external grep on skip-worktree entries Jeff King
2010-01-11 19:26 ` Fredrik Kuivinen
[not found] ` <4c8ef71001111119p253170f8q37bcd3708d894a62@mail.gmail.com>
2010-01-11 19:29 ` Linus Torvalds [this message]
2010-01-11 19:40 ` Fredrik Kuivinen
2010-01-11 20:07 ` Linus Torvalds
2010-01-11 21:07 ` Fredrik Kuivinen
2010-01-11 21:24 ` Linus Torvalds
2010-01-04 16:24 ` Linus Torvalds
2010-01-04 10:14 ` Nguyen Thai Ngoc Duy
2010-01-04 6:06 ` Mike Hommey
2010-01-04 7:04 ` Jeff King
2010-01-04 12:34 ` [PATCH 1/2] t7002: set test prerequisite "external-grep" if supported Nguyễn Thái Ngọc Duy
2010-01-07 2:37 ` Junio C Hamano
2010-01-07 4:29 ` Junio C Hamano
2010-01-07 13:27 ` Nguyen Thai Ngoc Duy
2010-01-07 14:04 ` Johannes Sixt
2010-01-07 14:26 ` Nguyen Thai Ngoc Duy
2010-01-04 12:34 ` [PATCH 2/2] t7002: add tests for skip-worktree fixes in commit a67e281 Nguyễn Thái Ngọc Duy
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