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SubjectRe: Need better is_better_time_interpolator() algorithm
Alex Williamson wrote:
> On Fri, 2005-08-26 at 08:39 -0700, Christoph Lameter wrote:
>
>
>>I think a priority is something useful for the interpolators. Some of
>>the decisions about which time sources to use also have criteria different
>>from drift/latency/jitter/cpu. F.e. timers may not survive various
>>power-saving configurations. Thus I would think that we need a priority
>>plus some flags.
>>
>>Some of the criteria for choosing a time source may be:
>
>
> Hi Christoph,
>
> I sent another followup to this thread with a patch containing a
> fairly crude algorithm that I think better explains my starting point.
> I'm sure the weighting and scaling factors need work, but I think many
> of the criteria you describe will favor the right clock.
>
>
>>1. If a system boots up with a single cpu then there is no question that
>>the ITC/TSC should be used because of the fast access.

We need to factor in frequency shifting here, especially if it happens
with out notice.


~
--
George Anzinger george@mvista.com
HRT (High-res-timers): http://sourceforge.net/projects/high-res-timers/
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