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From: Jeff Layton <jlayton@redhat.com>
To: Andrew Morton <akpm@osdl.org>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/3] i_ino uniqueness: alternate approach -- hash the inodes
Date: Wed, 24 Jan 2007 09:22:36 -0500	[thread overview]
Message-ID: <45B76BAC.4040408@redhat.com> (raw)
In-Reply-To: <20070123204648.204b1834.akpm@osdl.org>

Andrew Morton wrote:
> 
> What is the additional overhead, expressed in relative terms?  ie: as a percentage?

Short answer: ~3-4% in a not very scientific test.

Long answer: I timed 3 different runs of a program that created and then closed 
a pipe 10 million times on a patched and unpatched kernel. I then added up the
"system" times for each and divided them:

unpatched:
sys     1m53.959s
sys     1m56.083s
sys     1m48.055s

patched:
sys     1m56.899s
sys     1m57.027s
sys     1m57.031s

The result was 1.03803642150033866020.

-- Jeff

  reply	other threads:[~2007-01-24 14:22 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-01-16 18:57 Jeff Layton
2007-01-24  4:46 ` Andrew Morton
2007-01-24 14:22   ` Jeff Layton [this message]
2007-01-24 15:21     ` Eric Dumazet
2007-01-24 16:57       ` Jeff Layton
  -- strict thread matches above, loose matches on Subject: below --
2007-01-08 20:46 Jeff Layton
2007-01-10 20:58 ` Eric Sandeen
2006-12-29 19:10 Jeff Layton

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