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