Re: Variable timer tick rate?

From: David Schultz (das_at_FreeBSD.ORG)
Date: 10/18/03

  • Next message: Bruce Evans: "Re: Variable timer tick rate?" 
    Date: Sat, 18 Oct 2003 14:17:33 -0700
To: Nate Lawson <nate@root.org>

    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.
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  • Next message: Bruce Evans: "Re: Variable timer tick rate?"

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