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Date: Thu, 30 Nov 2006 23:34:32 +0000
From: John Birrell <jb@what-creek.com>
To: Poul-Henning Kamp <phk@phk.freebsd.dk>
Message-ID: <20061130233432.GA9667@what-creek.com>
References: <ekmr76$23g$1@sea.gmane.org> <1299.1164923821@critter.freebsd.dk>
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Cc: freebsd-arch@freebsd.org
Subject: Re: a proposed callout API
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On Thu, Nov 30, 2006 at 09:57:01PM +0000, Poul-Henning Kamp wrote:
> Most of Matts emails focus on the specifics of implementation whereas
> I have repeatedly stressed that my focus is on defining a good API
> for programmers to use which will allow us to isolate the implemetation
> so we can experiment with different strategies.
> 
> I will work with John to write up our spec and we will publish that
> along with the reasoning soon.

DTrace relies on the Solaris cyclic timer subsystem for core functionality.
Where the HPET is available on Intel arch machines, it is the cyclic 
driver that uses it.

Here is a link to a Sun blog describing some of the features they
implement: <http://blogs.sun.com/eschrock/date/20041127>

For DTrace to be as effective on FreeBSD as it is on Solaris, we need
similar functionality.

--
John Birrell