Re: Resolution of WdfTimer?

Don Burn schrieb:
"Joerg Hoppe" <jhoppe@xxxxxxxxxxxxxxxx> wrote in message news:eMd1k9iOHHA.4940@xxxxxxxxxxxxxxxxxxxxxxx
I'm porting an old WDM driver to KMDF.

Is WdfTimer still limited to a resolution of
KeQueryTimeIncrement(), which was approx 10 milliseconds in
former version of Windows?

If yes: how can I get a resolution of < 1 milliseconds?

WdfTimer is based on the the current timer, so there is no difference in resolution. Even if you play games the best timer resolution is 1 millisecond and the delays in the system mean you really do not get that.
I once heard a rumor that there are gaming/multimedia related time services which offer greater resolution.
Do you know more?

Btw: Years ago, under Win9x, there was "VTD_Begin_Min_Int_Period()" to enhance the timer. I really miss that.


.

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