Re: [PATCH] Greatly improve TSC calibration using a delayedworkqueue

[Andi Kleen]

On Tue, Nov 09, 2010 at 01:41:40PM -0800, john stultz wrote:
> > It may happen with opportunistic suspend if the system boots very fast.
> 
> Right, but a system using opportunistic suspend will have a hard enough
> time keeping close NTP sync on its own given the frequent switching
> between the fine-grained ntp adjusted clocksource during run-time and
> the coarse non-adjusted RTC/persisitent_clock while suspended.
> 
> So I think such a system would be fine it falls back to using just the
> boot-calibration for TSC freq rather then the refined calibration freq
> calculated by this patch (which will happen automatically if the refined
> calibration is off by 1%).
> 
> Does that seem like a reasonable tradeoff?

Yes it sounds good to me.  Some inaccuracy in this case is fine I guess.
Just major inaccuracy or a crash or hang wouldn't be good.

-Andi
-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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