Windows Time mechanism clarification. RRS feed

  • Question

  • Hi Team,

    May I know how does windows time works?

    During system boot up, after BIOS transfers the ownership to windows, does windows get the time value from CMOS RTC?

    After that, how does windows time tick-tock? using PCH's HPET(High Precision Event Timer) or CPU's TSC(Time Stamp Counter)?

    Does any interrupt or events will cause windows time pause? such as SMI?

    Any documents from windows to explain this mechanism.

    If I have to debug an issue relative with windows time, any way to monitor this time during system boot up?

    it is a data structure or run time register reading or something else?



    Thursday, August 20, 2015 5:22 AM


  • Hi Tarzan,

    Please refer to following article to understand windows time:

    Windows Time Service Technical Reference

    Best regards,

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    Niko Cheng
    TechNet Community Support

    • Marked as answer by Deason Wu Tuesday, September 8, 2015 2:00 AM
    Friday, August 21, 2015 8:48 AM