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From: Frank Sorenson <frank@tuxrocks.com>
To: Dag Nygren <dag@newtech.fi>
Cc: Nish Aravamudan <nish.aravamudan@gmail.com>,
	linux-kernel@vger.kernel.org
Subject: Re: nanosleep with small value
Date: Thu, 17 Nov 2005 12:47:09 -0700	[thread overview]
Message-ID: <437CDE3D.90606@tuxrocks.com> (raw)
In-Reply-To: <20051117191119.15126.qmail@dag.newtech.fi>

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Dag Nygren wrote:
> But what is the point of having a nanosleep() in that case when you could do
> just fine with usleep() ?

I'd suggest looking into the kthrt patches (which incorporates ktimers
and John Stultz's timeofday patches):  http://www.tglx.de/projects/ktimers/

Running your program, here are some results (latest git tree with the
latest kthrt and timeofday patches):

shortest of 10 runs as non-root:
real    0m0.418s
user    0m0.000s
sys     0m0.003s

longest of 10 runs as non-root:
real    0m0.794s
user    0m0.000s
sys     0m0.002s

shortest of 10 runs as root:
real    0m0.066s
user    0m0.001s
sys     0m0.007s

longest of 10 runs as root:
real    0m0.325s
user    0m0.000s
sys     0m0.004s

Frank
- --
Frank Sorenson - KD7TZK
Systems Manager, Computer Science Department
Brigham Young University
frank@tuxrocks.com
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  parent reply	other threads:[~2005-11-17 19:47 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <29495f1d0511171051q6088099drfe094817a01668e4@mail.gmail.com>
2005-11-17 19:11 ` nanosleep with small value Dag Nygren
2005-11-17 19:15   ` Randy.Dunlap
2005-11-17 19:17   ` Nish Aravamudan
2005-11-17 19:47   ` Frank Sorenson [this message]
2005-11-21  7:12     ` Dag Nygren
2005-11-17 20:25 Dag Nygren
  -- strict thread matches above, loose matches on Subject: below --
2005-11-17 16:30 Dag Nygren
2005-11-17 16:55 ` linux-os (Dick Johnson)
2005-11-17 17:32   ` Eric Piel
2005-11-17 17:12 ` Nish Aravamudan
2005-11-17 18:47   ` Dag Nygren

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