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Date: Sat, 18 Oct 2003 14:17:33 -0700
From: David Schultz <das@FreeBSD.ORG>
To: Nate Lawson <nate@root.org>
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cc: arch@FreeBSD.ORG
Subject: Re: Variable timer tick rate?
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On Sat, Oct 18, 2003, Nate Lawson wrote:
> This is an interesting approach.  If there are no upcoming timeouts,
> decrease the tick rate.  Of course, you have to amortize the cost of
> resetting the timer over the period of no ticks.
> 
> http://kerneltrap.org/node/view/1006

For the last couple of years, Solaris has had a 'cyclic' system
that automatically schedules the next clock interrupt to match the
next timeout.  This allows for arbitrarily high or low resolution
timers.  Even if we presently have subsystems that poll every
tick, high-resolution timers would be a neat thing to have, and it
should be possible to implement on all supported architectures
except pre-PPro i386's that don't have TSCs.