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From: Joe Perches <joe@perches.com>
To: Han-Wen Nienhuys <hanwen@google.com>
Cc: git <git@vger.kernel.org>
Subject: Re: grep vs git grep performance?
Date: Thu, 26 Oct 2017 08:55:21 -0700	[thread overview]
Message-ID: <1509033321.11245.3.camel@perches.com> (raw)
In-Reply-To: <CAFQ2z_P9bpw+Pc2DhJTCB8dxj-5JAKLE=nyvToGuiRA8wV66Wg@mail.gmail.com>

On Thu, 2017-10-26 at 17:11 +0200, Han-Wen Nienhuys wrote:
> On Thu, Oct 26, 2017 at 5:02 PM, Joe Perches <joe@perches.com> wrote:
> > Comparing a cache warm git grep vs command line grep
> > shows significant differences in cpu & wall clock.
> > 
> > Any ideas how to improve this?
> 
> Is git-grep multithreaded?

Yes, at least according to the documentation

$ git grep --help
[]
       grep.threads
           Number of grep worker threads to use. If unset (or set to 0), 8
           threads are used by default (for now).

> IIRC, grep -r uses multiple threads. (Do
> you have a 4-core machine?)

I have a 2 core machine with hyperthreading

$ cat /proc/cpuinfo
[]
model name	: Intel(R) Core(TM) i5-6200U CPU @ 2.30GHz
stepping	: 3
microcode	: 0xba
cpu MHz		: 2400.000
cache size	: 3072 KB
physical id	: 0
siblings	: 4
core id		: 0
cpu cores	: 2


  reply	other threads:[~2017-10-26 15:55 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-10-26 15:02 grep vs git grep performance? Joe Perches
2017-10-26 15:11 ` Han-Wen Nienhuys
2017-10-26 15:55   ` Joe Perches [this message]
2017-10-26 16:13 ` SZEDER Gábor
2017-10-26 16:20   ` Joe Perches
2017-10-26 16:58 ` Stefan Beller
2017-10-26 17:41   ` Joe Perches
2017-10-26 17:45     ` Stefan Beller
2017-10-27 17:22       ` Joe Perches
2017-10-27 22:11         ` Ævar Arnfjörð Bjarmason
2017-10-27 23:22           ` Joe Perches
2017-10-28  7:45             ` Ævar Arnfjörð Bjarmason

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