Re: QueryPerformanceFrequency

From: Tim Roberts <timr@xxxxxxxxx>
Date: Thu, 20 Mar 2008 20:14:15 -0700

Ondrej Spanel <OndrejSpanel.news@xxxxxxxxxxxxx> wrote:

While rdtsc is one possible implementation, on some CPUs/systems the QPC
needs to be implemented in a more complex manner (multiple CPUs, CPUs
with adaptive frequency, like seen first in notebooks and now in most
systems...)

Actually, on most systems with the multiprocessor HAL,
QueryPerformanceCounter simply calls rdtsc directly. And yes, it's
possible for QPC to go backwards slightly.
--
Tim Roberts, timr@xxxxxxxxx
Providenza & Boekelheide, Inc.
.

References:
- Re: QueryPerformanceFrequency
  - From: Alex Blekhman
- Re: QueryPerformanceFrequency
  - From: Ondrej Spanel

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