Re: [boost] Low-level precision timer proposal

From: Michael Fawcett (michael.fawcett_at_[hidden])
Date: 2006-05-15 15:29:45

On 5/15/06, Peter Dimov <pdimov_at_[hidden]> wrote:
> Silex wrote:
> >> The problem with QueryPerformanceCounter is that
> >> QueryPerformanceFrequency is not (AFAIK) required to return the same
> >> value every time. It may be CPU clock based, and a low power CPU can
> >> vary its frequency depending on load.
> >
> > No, "the frequency cannot change while the system is running."
> > (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winui/winui/windowsuserinterface/windowing/timers/timerreference/timerfunctions/queryperformancefrequency.asp)
>
> You are right, a variable frequency is explicitly disallowed in the
> documentation now. Most chipset bugs that affected QPC also don't seem to be
> an issue nowadays.

Does anyone know if the issue mentioned in this KB article is still relevant?

http://support.microsoft.com/default.aspx?scid=KB;EN-US;Q274323&

--Michael Fawcett