From: Thomas Rast <trast@student.ethz.ch>
To: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
Cc: "René Scharfe" <rene.scharfe@lsrfire.ath.cx>,
"Eric Herman" <eric@freesa.org>,
git@vger.kernel.org, "Junio C Hamano" <gitster@pobox.com>,
"Fredrik Kuivinen" <frekui@gmail.com>
Subject: Re: [PATCH v2 3/3] grep: disable threading in all but worktree case
Date: Fri, 23 Dec 2011 23:49:49 +0100 [thread overview]
Message-ID: <87mxaihpiq.fsf@thomas.inf.ethz.ch> (raw)
In-Reply-To: <CACBZZX6hboo4wu3fOs+CHnxsdmedxw72GFMVttQzmHzpcZbqoQ@mail.gmail.com> ("Ævar Arnfjörð Bjarmason"'s message of "Fri, 23 Dec 2011 23:37:55 +0100")
Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:
> On Fri, Dec 2, 2011 at 14:07, Thomas Rast <trast@student.ethz.ch> wrote:
>
>> I conjecture that this is caused by contention on
>> read_sha1_mutex. [...] So disable threading entirely when not
>> scanning the worktree
>
> Why does git-grep even need to keep a mutex to call read_sha1_file()?
> It's inherently a read-only operation isn't it? If the lock is needed
> because data is being shared between threads in sha1_file.c shouldn't
> we tackle that instead of completely disabling threading?
The problem is that all sorts of data is shared. See
http://thread.gmane.org/gmane.comp.version-control.git/186618
But I need to go through it again, there are some races and double locks
in the posted version.
--
Thomas Rast
trast@{inf,student}.ethz.ch
next prev parent reply other threads:[~2011-12-23 22:50 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-25 14:46 [PATCH] grep: load funcname patterns for -W Thomas Rast
2011-11-25 16:32 ` René Scharfe
2011-11-26 12:15 ` [PATCH] grep: enable multi-threading for -p and -W René Scharfe
2011-11-29 9:54 ` Thomas Rast
2011-11-29 13:49 ` René Scharfe
2011-11-29 14:07 ` Thomas Rast
2011-12-02 13:07 ` [PATCH v2 0/3] grep multithreading and scaling Thomas Rast
2011-12-02 13:07 ` [PATCH v2 1/3] grep: load funcname patterns for -W Thomas Rast
2011-12-02 13:07 ` [PATCH v2 2/3] grep: enable threading with -p and -W using lazy attribute lookup Thomas Rast
2011-12-02 13:07 ` [PATCH v2 3/3] grep: disable threading in all but worktree case Thomas Rast
2011-12-02 16:15 ` René Scharfe
2011-12-05 9:02 ` Thomas Rast
2011-12-06 22:48 ` René Scharfe
2011-12-06 23:01 ` [PATCH 4/2] grep: turn off threading for non-worktree René Scharfe
2011-12-07 4:42 ` Jeff King
2011-12-07 17:11 ` René Scharfe
2011-12-07 18:28 ` Jeff King
2011-12-07 20:11 ` J. Bruce Fields
2011-12-07 20:45 ` Jeff King
2011-12-07 8:12 ` Thomas Rast
2011-12-07 17:00 ` René Scharfe
2011-12-10 13:13 ` Pete Wyckoff
2011-12-12 22:37 ` René Scharfe
2011-12-07 4:24 ` [PATCH v2 3/3] grep: disable threading in all but worktree case Jeff King
2011-12-07 16:52 ` René Scharfe
2011-12-07 18:10 ` Jeff King
2011-12-07 8:11 ` Thomas Rast
2011-12-07 16:54 ` René Scharfe
2011-12-12 21:16 ` [PATCH v3 0/3] grep attributes and multithreading Thomas Rast
2011-12-12 21:16 ` [PATCH v3 1/3] grep: load funcname patterns for -W Thomas Rast
2011-12-12 21:16 ` [PATCH v3 2/3] grep: enable threading with -p and -W using lazy attribute lookup Thomas Rast
2011-12-16 8:22 ` Johannes Sixt
2011-12-16 17:34 ` Junio C Hamano
2011-12-12 21:16 ` [PATCH v3 3/3] grep: disable threading in non-worktree case Thomas Rast
2011-12-12 22:37 ` [PATCH v3 0/3] grep attributes and multithreading René Scharfe
2011-12-12 23:44 ` Junio C Hamano
2011-12-13 8:44 ` Thomas Rast
2011-12-23 22:37 ` [PATCH v2 3/3] grep: disable threading in all but worktree case Ævar Arnfjörð Bjarmason
2011-12-23 22:49 ` Thomas Rast [this message]
2011-12-24 1:39 ` Ævar Arnfjörð Bjarmason
2011-12-24 7:07 ` Jeff King
2011-12-24 10:49 ` Nguyen Thai Ngoc Duy
2011-12-24 10:55 ` Nguyen Thai Ngoc Duy
2011-12-24 13:38 ` Jeff King
2011-12-25 3:32 ` Nguyen Thai Ngoc Duy
2011-12-02 17:34 ` [PATCH v2 0/3] grep multithreading and scaling Jeff King
2011-12-05 9:38 ` Thomas Rast
2011-12-05 20:16 ` Thomas Rast
2011-12-06 0:40 ` Jeff King
2011-12-02 20:02 ` Eric Herman
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