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Editorial Team
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Asked: 2026-05-16T05:02:03+00:00

The idea is that an existing project uses timeGetTime() (for windows targets) quite frequently.

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The idea is that an existing project uses timeGetTime() (for windows targets) quite frequently. 

milliseconds = timeGetTime();

Now, this could be replaced with 

double tmp = (double) lpPerformanceCount.QuadPart/ lpFrequency.QuadPart; 
milliseconds = rint(tmp * 1000);

with lpPerformanceCount.QuadPart and lpFrequency.QuadPart being taken from the use of a single call to QueryPerformanceCounter() and QueryPerformanceFrequency().

I know Windows’ internals are kind of voodoo, but can someone decipher which of the two is more accurate or/and has more overheads?

I suspect accuracy might be same but QueryPerformanceCounter might have less overheads. But I have no hard data to back it up.

Of course I wouldn’t be surprised if the opposite is true.

If overheads are tiny in any way I would be more interested on whether there’s any difference in accuracy.

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1 Answer

  1. Editorial Team

    The accuracy of timeGetTime() is variable, based on the last used timeBeginPeriod. It will never be better than one millisecond. QueryPerformanceCounter is variable too, depending on hardware support. It will never be worse than about a microsecond.

    Neither of them have notable overhead, QPC is probably a bit heavier. Whether that’s significant to you is quite unclear from your question. I doubt it, but measure. With QPC.

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