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Sharing the system

I have an MFC application that I wrote that is a real number cruncher. It may run for several hours. It seems to hog the system to such a degree that the system is not really usable for any other purposes. How should I make my application be nicer to other applications? What do I need to include in my loops that will allow other applications to get some CPU? I can accept some speed loss in my application if need be.

Thanks!

Dave P

PS: I would apreciate (and need!) specific details.

Bridge

Put Sleep(x) every now and again in you code. x=10to100

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doin

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naveenkohli

Here is some sample code which creates a thead.. do your number crunching. And when it is done, it posts a message for the parent window so that the parent can take the post crunch actins on it :))

// In Header fIle :))

#define WM_USER_THREAD_FINISHED WM_USER+0x100

UINT ThreadFunc (LPVOID pParam);
int Sieve (int nMax);

typedef struct tagTHREADPARMS {
int nMax;
      HWND hWnd;
} THREADPARMS;

afx_msg LONG OnThreadFinished (WPARAM wParam, LPARAM lParam);

// Source file

BEGIN_MESSAGE_MAP(CMyApp, CWinApp)
      //{{AFX_MSG_MAP(CMyApp)
      //}}AFX_MSG_MAP
      ON_MESSAGE (WM_USER_THREAD_FINISHED, OnThreadFinished)
END_MESSAGE_MAP()

void CMyApp::OnStartCrunch()
{
      THREADPARMS* ptp = new THREADPARMS;
      ptp->nMax = nMax;
      ptp->hWnd = m_hWnd;
      AfxBeginThread (ThreadFunc, ptp);
}

LONG CMyApp::OnThreadFinished (WPARAM wParam, LPARAM lParam)
{
      int result = (int) wParam;

return 0;
}

UINT ThreadFunc (LPVOID pParam)
{
      THREADPARMS* ptp = (THREADPARMS*) pParam;
      int nMax = ptp->nMax;
      HWND hWnd = ptp->hWnd;
      delete ptp;

int nCount = CrunchNumbers (nMax);
::PostMessage (hWnd, WM_USER_THREAD_FINISHED, (WPARAM) nCount, 0);
return 0;
}

int CrunchNumbers (int nMax)
{
PBYTE pBuffer = new BYTE[nMax + 1];
::FillMemory (pBuffer, nMax + 1, 1);

      // Do your VOODOO :))

/*
int nLimit = 2;
while (nLimit * nLimit < nMax)
nLimit++;

for (int i=2; i<=nLimit; i++) {
if (pBuffer[i]) {
for (int k=i + i; k<=nMax; k+=i)
pBuffer[k] = 0;
}
}

int nCount = 0;
for (i=2; i<=nMax; i++)
if (pBuffer[i])
nCount++;
*/
delete[] pBuffer;
return nCount;
}