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Date: Wed, 2 Jan 2013 17:22:06 +0100
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Alexander Motin <mav@FreeBSD.org>
Subject: Re: [RFC/RFT] calloutng
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On Wed, Jan 02, 2013 at 03:11:05PM +0200, Alexander Motin wrote:
...
> > First of all, if you know that there is already a hardclock/statclock/*
> > scheduled in [T_X, T_X+D] you just reuse that. This particular bullet
> > was ""no event scheduled in [T_X, T_X+D]" so you need to generate
> > a new one.
> 
> That is true, but my main point was about merging with external events,
> which I can't predict and the only way to merge is increase sleep period,
> hoping for better.

ok, now i understand why you want to schedule for T_X+D.

Probably one way to close this discussion would be to provide
a sysctl so the sysadmin can decide which point in the interval
to pick when there is no suitable callout already scheduled.

cheers
luigi

-----------------------------------------+-------------------------------
  Prof. Luigi RIZZO, rizzo@iet.unipi.it  . Dip. di Ing. dell'Informazione
  http://www.iet.unipi.it/~luigi/        . Universita` di Pisa
  TEL      +39-050-2211611               . via Diotisalvi 2
  Mobile   +39-338-6809875               . 56122 PISA (Italy)
-----------------------------------------+-------------------------------