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  1. Qt
  2. QTBUG-42365

QElapsedTimer::elapsed() inaccurate by up to 1 millisecond

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    • Icon: Bug Bug
    • Resolution: Done
    • Icon: P3: Somewhat important P3: Somewhat important
    • 5.5.0
    • 4.8.6, 5.3.2
    • Core: Date/Time
    • None
    • Arch Linux x86
      Intel Pentium 4 3 GHz
    • 51ddaabb81ae55d13aaabfdf45ee7db4d7c9bba2

      If you compare QElapsedTimer::elapsed() with QElapsedTimer::nsecsElapsed(), you will find QElapsedTimer::elapsed() to be inaccurate by up to 1 millisecond:

      $ ./elapsedtest
Wait for 53 ms
QElapsedTimer::elapsed(): 53
QElapsedTimer::nsecsElapsed(): 53096276
$ ./elapsedtest
Wait for 53 ms
QElapsedTimer::elapsed(): 54
QElapsedTimer::nsecsElapsed(): 53093277
$ ./elapsedtest
Wait for 53 ms
QElapsedTimer::elapsed(): 53
QElapsedTimer::nsecsElapsed(): 53094545
$ ./elapsedtest
Wait for 53 ms
QElapsedTimer::elapsed(): 54
QElapsedTimer::nsecsElapsed(): 53089063

        1. elapsedtest.cpp
          0.6 kB
        For Gerrit Dashboard: QTBUG-42365
        # Subject Branch Project Status CR V
        98791,2 QElapsedTimer/Unix: Improve accuracy for millisecond values 5.4 qt/qtbase Status: ABANDONED 0 0
        98810,3 QElapsedTimer/Unix: Improve accuracy for millisecond values dev qt/qtbase Status: MERGED +2 0

            net147 Jonathan Liu
            net147 Jonathan Liu
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              Created:
              Updated:
              Resolved:

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