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From: des@des.no (Dag-Erling =?iso-8859-1?Q?Sm=F8rgrav?=)
To: Robert Watson <rwatson@FreeBSD.org>
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Date: Mon, 30 Apr 2007 22:42:17 +0200
In-Reply-To: <20070428121554.T28395@fledge.watson.org> (Robert Watson's
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Cc: current@freebsd.org, Hartmut Brandt <Hartmut.Brandt@dlr.de>,
	Tim Kientzle <kientzle@freebsd.org>, David G Lawrence <dg@dglawrence.com>,
	"Jesper B. Rosenkilde" <jbr@humppa.dk>
Subject: Re: Suggestions on Avoiding syscall Overhead
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Robert Watson <rwatson@FreeBSD.org> writes:
> Unfortunately, this sort of thing can't be expressed using the
> standard APIs. This leaves us two choices: allow the behavior of
> standard APIs to be configured at some granularity, or introduce new
> APIs.  My feeling is we should prefer new APIs, and suggest that
> programmers use those.  Take a look at sys/sys/time.h:1.71 for an
> example of what might make sense.

I'm not sure this is a good example.

There is already a suitable extensible API: clock_gettime(), which is
part of SUSv3.  Define new CLOCK_* constants for requesting a faster,
less precise timecounter, and if you feel like it, submit it to X/Open
for inclusion in the next version of the SUS.

DES
--=20
Dag-Erling Sm=F8rgrav - des@des.no