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Looking for PreciseTimer.zip - Visual C++


CodeExplorer

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CodeExplorer
CodeExplorer

On the second post it was time measurement, maybe some one will need that.

I've created class PreciseTimer from first post, first link (attached).
And some usage here:

void CAlocLogDlg::OnButton9()
{
    // TODO: Add your control notification handler code here

for (int i=0;i<2000000000;i++)
{
PreciseTimer* pt = new PreciseTimer();

LARGE_INTEGER iStart, iStop;
QueryPerformanceCounter(&iStart);

pt->Wait(5); // is there anything to wait on? ... then wait
QueryPerformanceCounter(&iStop);

long diference = (long)iStop.QuadPart-(long)iStart.QuadPart;

if (diference>5)
{
int no_way = 1;
}


}

}

 

PreciseTimer.zip

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CodeExplorer

timeSetEvent https://msdn.microsoft.com/en-us/library/windows/desktop/dd757634(v=vs.85).aspx
suppose to be precise
 

void CALLBACK TimerFunction(UINT wTimerID, UINT msg,
    DWORD dwUser, DWORD dw1, DWORD dw2)
    {

char conv_str[50];
wsprintf(conv_str,"%d", GetTickCount());  // convert number to dec string
InsertStringToList(conv_str);

    }

void CAlocLogDlg::OnButton9()
{
// TODO: Add your control notification handler code here

// https://msdn.microsoft.com/en-us/library/windows/desktop/dd757634%28v=vs.85%29.aspx
MMRESULT m_idEvent = timeSetEvent(1, 0,
        TimerFunction,
        (DWORD)this,
        TIME_PERIODIC);
}

Actually is not precise at all! Still maybe someone will find the solutions posted above useful, but not me!

The best solution I found so far is CreateThread on an infinite loop:
 

DWORD   dwThreadId;
HANDLE hThread = CreateThread(
            NULL,                   // default security attributes
            0,                      // use default stack size  
            MyThreadFunction,       // thread function name
            NULL,          // argument to thread function
            0,                      // use default creation flags
            &dwThreadId);   // returns the thread identifier 

But there is a problem: to many CPU resource are consumed.
I've thinked at something like if the time passed since last value found has a specific value do Sleep(1).

 

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CodeExplorer

So here is my solution:
LastTimeValueFound = GetTickCount();
called twice after each variable was readed,

and on the loop I do this:

if (LastTimeValueFound==0||(GetTickCount()-LastTimeValueFound)>100)
{
Sleep(1);
}

CPU usage was once 20% for a short time - when Api logged,
When no Api logged 0% CPU usage,
tracing time 2 minutes for a nasty Asprotect unpackme.
 

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