Re: [PATCH] Dynamic tick, version 050127-1

From: Tony Lindgren
Date: Tue Feb 01 2005 - 18:44:31 EST


* Lee Revell <rlrevell@xxxxxxxxxxx> [050201 12:20]:
> On Thu, 2005-01-27 at 13:29 -0800, Tony Lindgren wrote:
> > Hi all,
> >
> > Thanks for all the comments, here's an updated version of the dynamic
> > tick patch.
>
> Hi,
>
> I was wondering how Windows handles high res timers, if at all. The
> reason I ask is because I have been reverse engineering a Windows ASIO
> driver, and I find that if the latency is set below about 5ms, by
> examining the kernel timer queue with SoftICE I can see that several
> kernel timers with 1ms period are created. (Presumably the sound card's
> interval timer is used for longer periods).
>
> But, I have seen people mention in the "singing capacitor" threads on
> this list that Windows uses 100 for HZ.
>
> So, how do they implement 1ms timers with a 10ms tick rate? Does
> Windows dynamically reprogram the PIT as well?

No idea, but it would probably show up by adding some debug code
some an emulator like Bochs?

Tony
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