In bpo-21302, the Windows implementation of time.sleep() was modified to use a waitable timer:

New changeset 58f8adfda3c2b42f654a55500e8e3a6433cb95f2 by Victor Stinner in branch 'main':
bpo-21302: time.sleep() uses waitable timer on Windows (GH-28483)
https://github.com/python/cpython/commit/58f8adfda3c2b42f654a55500e8e3a6433cb95f2

It now calls the functions:

* CreateWaitableTimerW()
* SetWaitableTimer()
* WaitForMultipleObjects()

While SetWaitableTimer() has a resolution of 100 ns, the timer has a resolution of 15.6 ms in practice.

We could use the undocumented CREATE_WAITABLE_TIMER_HIGH_RESOLUTION flag with CreateWaitableTimerEx(). See: https://bugs.python.org/issue21302#msg403550

See also:

* https://randomascii.wordpress.com/2013/07/08/windows-timer-resolution-megawatts-wasted/
* https://vstinner.readthedocs.io/windows.html#time

See also: https://groups.google.com/a/chromium.org/g/scheduler-dev/c/0GlSPYreJeY

The Go programming language called timeBeginPeriod(1) to get more accurate timers. With the following change, it can now use a high resolution timer (CREATE_WAITABLE_TIMER_HIGH_RESOLUTION) to sleep:
https://go-review.googlesource.com/c/go/+/248699/

See also bpo-19007: "precise time.time() under Windows 8: use GetSystemTimePreciseAsFileTime".

It's up to the core devs whether or not Python should try to use a high-resolution timer, which is currently undocumented in the Windows API and implemented only in recent releases of Windows 10 and 11. But if this does get supported, the code should fall back on creating a normal timer if CREATE_WAITABLE_TIMER_HIGH_RESOLUTION makes the call fail. For example:

    #ifndef CREATE_WAITABLE_TIMER_HIGH_RESOLUTION
    #define CREATE_WAITABLE_TIMER_HIGH_RESOLUTION 0x00000002
    #endif

        LARGE_INTEGER relative_timeout;
        // No need to check for integer overflow, both types are signed
        assert(sizeof(relative_timeout) == sizeof(timeout_100ns));
        // SetWaitableTimerEx(): a negative due time is relative
        relative_timeout.QuadPart = -timeout_100ns;
        DWORD flags = CREATE_WAITABLE_TIMER_HIGH_RESOLUTION;

    create_timer:

        HANDLE timer = CreateWaitableTimerExW(NULL, NULL, flags, TIMER_ALL_ACCESS);
        if (timer == NULL)
        {
            if (flags && GetLastError() == ERROR_INVALID_PARAMETER) {
                // CREATE_WAITABLE_TIMER_HIGH_RESOLUTION is not supported.
                flags = 0;
                goto create_timer;
            }
            PyErr_SetFromWindowsErr(0);
            return -1;
        }

        if (!SetWaitableTimerEx(timer, &relative_timeout,
              0,          // no period; the timer is signaled once
              NULL, NULL, // no completion routine
              NULL,       // no wake context; do not resume from suspend
              0))         // no tolerable delay for timer coalescing
        {
            PyErr_SetFromWindowsErr(0);
            goto error;
        }

A similar solution was introduced in VirtualBox some months ago. Soon, i could get back my Windows 10 developing PC and i can try this things.

https://www.virtualbox.org/browser/vbox/trunk/src/VBox/Runtime/r3/win/timer-win.cpp#L312

AS-IS:
average:  0.015609736680984497

TO-BE:
average:  2.7387380599975585e-05

Impressive result :)

New changeset 55868f1a335cd3853938082a5b25cfba66563135 by Dong-hee Na in branch 'main':
bpo-45429: Support CREATE_WAITABLE_TIMER_HIGH_RESOLUTION if possible (GH-29203)
https://github.com/python/cpython/commit/55868f1a335cd3853938082a5b25cfba66563135

New changeset fc4474e45eecbea8e88095f28c98c5d56438d841 by Dong-hee Na in branch 'main':
bpo-45429: Merge whatsnew about time.sleep (GH-29589)
https://github.com/python/cpython/commit/fc4474e45eecbea8e88095f28c98c5d56438d841

messages: + msg404936