seltsames Verhalten mit chrono :: high_resolution_clock :: now ()

Question

Jan 31, 2014, 01:19 AM

seltsames Verhalten mit chrono :: high_resolution_clock :: now ()

Ich habe mir verschiedene Spiel-Timing-Loop-Methoden angesehen, z. Glenn Fiedler und DeWitter. Ich fand kritische Bereiche aufgrund meiner eigenen C ++ - Kenntnisse schwierig zu verstehen. Damit begann ich zu versuchen, meine eigene Methode zu implementieren. Ich dachte mir eine gute Möglichkeit, etwas über diese Methoden zu verstehen.

[edit1: Ich verwende CodeBlocks IDE mit minGW-w64 (x64-4.8.1-posix-seh-rev5) als Compiler]

[edit2: Code- und Ausgabefenster um einen 3. Timer, QueryPerformanceCounter, erweitert]

Bei dem Versuch, dies zu erreichen, bin ich auf folgendes Problem gestoßen:

Minimaler Code:

#include <chrono>
#include <iostream>
#include <windows.h>
#include <stdio.h>

using namespace std;
using namespace chrono;

LARGE_INTEGER startqpc, stopqpc, li;
double PCFreq = 0.0;


void print()
{
for (int p=0; p<1000000; ) p += 1;  //adjust till ms (steady) returns 1-2ms
}

int main()
{
    for(int x=0; x<200; x += 1)
    {
    steady_clock::time_point start = steady_clock::now();
    auto timePoint1 = chrono::high_resolution_clock::now();

    if(!QueryPerformanceFrequency(&li))
        cout << "QueryPerformanceFrequency failed!\n";
    PCFreq = double(li.QuadPart)/1000.0;
    QueryPerformanceCounter(&startqpc);

    print();

    steady_clock::time_point finish = steady_clock::now();
    auto timePoint2 = chrono::high_resolution_clock::now();
    QueryPerformanceCounter(&stopqpc);
    auto elapsedTime(timePoint2 - timePoint1);
    double diff = (stopqpc.QuadPart - startqpc.QuadPart)/PCFreq;

    cout << "Elapsed time: "
              << duration_cast<milliseconds>(finish - start).count() << "ms (steady)   "
              << chrono::duration_cast<chrono::duration<float, milli >> (elapsedTime).count() << "ms (hires)   "
              << diff << " (qpc) \n";

    }
}

Zu Vergleichszwecken werden im obigen Code zwei Timer verwendet.

Auf meinem PC ist die Ausgabe davon wie folgt:

Elapsed time: 1ms (steady)   0ms (hires)   1.8429 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8429 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85152 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.85557 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.59283 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.25573 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85072 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85422 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.85099 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.31582 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.84964 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.52466 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 2ms (steady)   15.6ms (hires)   2.25169 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.26974 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84991 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84667 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.89518 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.87874 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.92213 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.87605 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.03126 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.87659 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.88467 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.24899 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.30316 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23579 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93263 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23552 (qpc)
Elapsed time: 2ms (steady)   15.6ms (hires)   2.42118 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.24522 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23471 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23848 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93425 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9329 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.85126 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.35355 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23687 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23633 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.2374 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23498 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85449 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.0097 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.15441 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93263 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93425 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23579 (qpc)
Elapsed time: 2ms (steady)   15.6ms (hires)   2.04554 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.1121 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.01779 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.07222 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9329 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93425 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.95015 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.95177 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84587 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85233 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.88278 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84667 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.88629 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.8588 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.06225 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23633 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93317 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.06009 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.86284 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93425 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.02803 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.26839 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93398 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.93641 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93371 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93344 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9329 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.02345 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.08731 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9356 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93398 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.09 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93371 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.03072 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.19213 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85287 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9321 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93344 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93317 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93344 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93263 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.42711 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.9418 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9356 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.08947 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9329 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93614 (qpc)
Elapsed time: 2ms (steady)   15.6ms (hires)   2.27702 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93614 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93317 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.08974 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.92698 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93317 (qpc)
Elapsed time: 2ms (steady)   15.6ms (hires)   2.09054 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.96066 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.96093 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1ms (steady)   15.6001ms (hires)   1.91835 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84587 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.85233 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93317 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93317 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.23552 (qpc)
Elapsed time: 1ms (steady)   15.6ms (hires)   1.93102 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.07033 (qpc)
Elapsed time: 2ms (steady)   0ms (hires)   2.09405 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.9329 (qpc)
Elapsed time: 1ms (steady)   0ms (hires)   1.93263 (qpc)

Process returned 0 (0x0)   execution time : 0.484 s
Press any key to continue.

Verwendenduration_cast<microseconds>(finish - start).count()/1000.0 für die steady_clock sehen wir folgendes: -

Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1.843ms (steady)   0ms (hires)   1.84317 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.846ms (steady)   0ms (hires)   1.84694 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1.877ms (steady)   0ms (hires)   1.87685 (qpc)
Elapsed time: 1.916ms (steady)   15.6ms (hires)   1.9162 (qpc)
Elapsed time: 1.906ms (steady)   0ms (hires)   1.90623 (qpc)
Elapsed time: 1.905ms (steady)   0ms (hires)   1.90515 (qpc)
Elapsed time: 1.909ms (steady)   0ms (hires)   1.90919 (qpc)
Elapsed time: 1.905ms (steady)   0ms (hires)   1.90542 (qpc)
Elapsed time: 1.905ms (steady)   0ms (hires)   1.90488 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.943ms (steady)   15.6ms (hires)   1.94287 (qpc)
Elapsed time: 1.872ms (steady)   0ms (hires)   1.87281 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.846ms (steady)   15.6001ms (hires)   1.8464 (qpc)
Elapsed time: 1.875ms (steady)   0ms (hires)   1.87497 (qpc)
Elapsed time: 2.033ms (steady)   0ms (hires)   2.03449 (qpc)
Elapsed time: 1.922ms (steady)   0ms (hires)   1.92293 (qpc)
Elapsed time: 1.922ms (steady)   0ms (hires)   1.92293 (qpc)
Elapsed time: 1.926ms (steady)   0ms (hires)   1.92698 (qpc)
Elapsed time: 2.004ms (steady)   15.6ms (hires)   2.00485 (qpc)
Elapsed time: 1.847ms (steady)   0ms (hires)   1.84748 (qpc)
Elapsed time: 1.847ms (steady)   0ms (hires)   1.84748 (qpc)
Elapsed time: 1.848ms (steady)   0ms (hires)   1.84856 (qpc)
Elapsed time: 1.849ms (steady)   0ms (hires)   1.84937 (qpc)
Elapsed time: 2.299ms (steady)   0ms (hires)   2.29938 (qpc)
Elapsed time: 3.497ms (steady)   15.6ms (hires)   3.49664 (qpc)
Elapsed time: 3.528ms (steady)   0ms (hires)   3.52843 (qpc)
Elapsed time: 2.299ms (steady)   0ms (hires)   2.29857 (qpc)
Elapsed time: 1.849ms (steady)   0ms (hires)   1.84937 (qpc)
Elapsed time: 1.848ms (steady)   0ms (hires)   1.84856 (qpc)
Elapsed time: 1.848ms (steady)   0ms (hires)   1.84856 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84263 (qpc)
Elapsed time: 1.854ms (steady)   0ms (hires)   1.85395 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.843ms (steady)   0ms (hires)   1.84371 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.8429 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.843ms (steady)   0ms (hires)   1.8429 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.861ms (steady)   0ms (hires)   1.86123 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 2.058ms (steady)   0ms (hires)   2.05848 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.881ms (steady)   0ms (hires)   1.88144 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.843ms (steady)   0ms (hires)   1.84371 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84209 (qpc)
Elapsed time: 1.896ms (steady)   0ms (hires)   1.89653 (qpc)
Elapsed time: 1.842ms (steady)   0ms (hires)   1.84236 (qpc)
Elapsed time: 1.843ms (steady)   0ms (hires)   1.84398 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.886ms (steady)   0ms (hires)   1.88656 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.85ms (steady)   15.6ms (hires)   1.85099 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.848ms (steady)   15.6001ms (hires)   1.84883 (qpc)
Elapsed time: 2.066ms (steady)   0ms (hires)   2.06683 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.888ms (steady)   0ms (hires)   1.88817 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.853ms (steady)   15.6ms (hires)   1.85341 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 2.056ms (steady)   0ms (hires)   2.05605 (qpc)
Elapsed time: 1.88ms (steady)   0ms (hires)   1.8809 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.882ms (steady)   0ms (hires)   1.88224 (qpc)
Elapsed time: 1.849ms (steady)   15.6ms (hires)   1.85018 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 2.243ms (steady)   0ms (hires)   2.24333 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.849ms (steady)   15.6ms (hires)   1.85018 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 2.109ms (steady)   0ms (hires)   2.10914 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 2.006ms (steady)   0ms (hires)   2.00647 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.852ms (steady)   15.6ms (hires)   1.8526 (qpc)
Elapsed time: 2.534ms (steady)   0ms (hires)   2.53463 (qpc)
Elapsed time: 2.368ms (steady)   0ms (hires)   2.3681 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.853ms (steady)   15.6ms (hires)   1.85368 (qpc)
Elapsed time: 1.843ms (steady)   0ms (hires)   1.84371 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84533 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.852ms (steady)   15.6ms (hires)   1.85233 (qpc)
Elapsed time: 1.849ms (steady)   0ms (hires)   1.8491 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84587 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.891ms (steady)   15.6001ms (hires)   1.89168 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.846ms (steady)   0ms (hires)   1.84587 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires),   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.846ms (steady)   15.6ms (hires)   1.8464 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84587 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.848ms (steady)   15.6ms (hires)   1.84829 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.846ms (steady)   15.6ms (hires)   1.84614 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.8456 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84506 (qpc)
Elapsed time: 1.872ms (steady)   15.6001ms (hires)   1.87281 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84452 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84587 (qpc)
Elapsed time: 1.844ms (steady)   0ms (hires)   1.84425 (qpc)
Elapsed time: 1.845ms (steady)   0ms (hires)   1.84479 (qpc)

Process returned 0 (0x0)   execution time : 0.499 s
Press any key to continue

Beachten Sie, wie der hochauflösende Takt zwischen 0 und 15,6 ms schwankt, und beachten Sie den steady_clock-Vergleich.

Das Problem, das ich habe, ist, dass, wenn ich eine zeitlich festgelegte Spielschleife implementieren würde, bei der der update () - Code die Entitätspositionen mit genau 1000/60 (60 Aktualisierungszyklen pro Sekunde) aktualisiert, dh alle 16,666etc ms - dann ist dies sehr In der Nähe des zurückgegebenen Zeitgebers schwankender Wert! Das eigentliche Problem ist, dass, wenn ich auch einen Akkumulator implementiere, um sowohl Spielschleifen-Frame-Zeiten unter 1000/60 ms als auch verbleibende Reste nach Abschluss von update () zu berücksichtigen, die Update-Schleife früher - und zu unregelmäßigen Zeitpunkten - aufgerufen wird es sollte.

Gibt es ein Problem mit dem obigen Minimalcode, und wenn nicht, sollte ich mich um eine ordnungsgemäße Implementierung zur festgelegten Zeit kümmern? Gibt es zusätzlich und falls relevant eine Möglichkeit, ein Programm / einen Thread zu isolieren, damit es nicht durch System-IRQ oder andere Abfrageereignisse unterbrochen wird? Ich vermute, der Timer des Mieters kann solchen Unterbrechungen unterliegen.