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SubjectRe: Missed jiffies
"H. Peter Anvin" wrote:
>
> Followup to: <3C6E833F.1A888B3C@mvista.com>
> By author: george anzinger <george@mvista.com>
> In newsgroup: linux.dev.kernel
> >
> > One of the nasty problems, especially with machines such as yours (i.e.
> > lap tops), is the fact that TSC is NOT clocked at a fixed rate. It is
> > affected by throttling (reduced in 12.5% increments) and by power
> > management.
>
> If the TSC is affected by HLT, throttling, or C2 power management, the
> TSC is broken (as it is on Cyrix chips, for example.) The TSC usually
> *is* affected by C3 power management, but the OS should be aware of
> C3.
>
> -hpa
Gosh I would LIKE to think this is true. Could you give a reference? I
believe Andrew Grover thinks that what I have stated is true. If I am
wrong, it will make the high-res-timers MUCH more acceptable as the TSC
overhead is MUCH lower that the ACPI pm timer.

Do I have this right Andrew?
--
George george@mvista.com
High-res-timers: http://sourceforge.net/projects/high-res-timers/
Real time sched: http://sourceforge.net/projects/rtsched/
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