Question on KeQueryInterruptTime

NTDEV
1

What is the resolution of KeQueryInterruptTime() ? From MSDN documentation, the timer value is incremented at each clock interrupt by the length of a clock tick. KeQueryTimeIncrement() (which is the length of clock tick) returns 16 ms for me on my system.

I am trying to find out the time difference between 2 ISR (passive level) invocations. On both occasions , I see that KeQueryInterruptTime is returning the same value.

Kindly let me know

Thanks,
manoj

2

If your ISR always runs on the same processor, KeQueryPerformanceCounter will give you much better precision. There may be (or not) inconsistency if you call it on different processors.

3

KeQueryTimeIncrement()

  • Jake

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of xxxxx@gmail.com
Sent: Thursday, October 24, 2013 3:07 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] Question on KeQueryInterruptTime

What is the resolution of KeQueryInterruptTime() ? From MSDN documentation, the timer value is incremented at each clock interrupt by the length of a clock tick. KeQueryTimeIncrement() (which is the length of clock tick) returns 16 ms for me on my system.

I am trying to find out the time difference between 2 ISR (passive level) invocations. On both occasions , I see that KeQueryInterruptTime is returning the same value.

Kindly let me know

Thanks,
manoj

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