BOUNCE rtl@rtlinux.org: Approval required: (fwd)

[Der Herr Hofrat <der.herr@hofr.at>]

>From owner-rtl Tue Jul 10 10:48:13 2001
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Date: Tue, 10 Jul 2001 17:47:14 +0100 (BST)
From: =?iso-8859-1?q?Raul?= <raulrtl@yahoo.co.uk>
Subject: usleep, rtl_delay and clock_nanosleep performance
To: Real Time Linux <rtl@rtlinux.org>
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Hi all
I need a 25 usec delay within a rt thread. Somewhere I
read that rtl_delay() should not be used (I take it
because it is blocking), instead usleep() or
clock_nanosleep() are preferable. However when I
measured the actual delay of these functions I found
that clock_nanosleep and usleep make a wait of nearly
50 usec (somthing to do with the scheduling?) whereas
rtl_delay() is more precise, with a wait of 27 usec. 
Is the use of a non-blocking function with a poorer
precission a compromise? Is rtl_delay not advisable to
use under any circunstances, even if I guarantee that
the rt thread period will be larger than 25 usec?
thanks again
Raul

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