Mengumpulkan Informasi Penggunaan Memori Untuk Proses

Untuk menentukan efisiensi aplikasi, Anda mungkin ingin memeriksa penggunaan memorinya. Kode sampel berikut menggunakan fungsiGetProcessMemoryInfo untuk mendapatkan informasi tentang penggunaan memori proses.

#include <windows.h>
#include <stdio.h>
#include <psapi.h>

// To ensure correct resolution of symbols, add Psapi.lib to TARGETLIBS
// and compile with -DPSAPI_VERSION=1

void PrintMemoryInfo( DWORD processID )
{
    HANDLE hProcess;
    PROCESS_MEMORY_COUNTERS pmc;

    // Print the process identifier.

    printf( "\nProcess ID: %u\n", processID );

    // Print information about the memory usage of the process.

    hProcess = OpenProcess(  PROCESS_QUERY_INFORMATION |
                                    PROCESS_VM_READ,
                                    FALSE, processID );
    if (NULL == hProcess)
        return;

    if ( GetProcessMemoryInfo( hProcess, &pmc, sizeof(pmc)) )
    {
        printf( "\tPageFaultCount: 0x%08X\n", pmc.PageFaultCount );
        printf( "\tPeakWorkingSetSize: 0x%08X\n", 
                  pmc.PeakWorkingSetSize );
        printf( "\tWorkingSetSize: 0x%08X\n", pmc.WorkingSetSize );
        printf( "\tQuotaPeakPagedPoolUsage: 0x%08X\n", 
                  pmc.QuotaPeakPagedPoolUsage );
        printf( "\tQuotaPagedPoolUsage: 0x%08X\n", 
                  pmc.QuotaPagedPoolUsage );
        printf( "\tQuotaPeakNonPagedPoolUsage: 0x%08X\n", 
                  pmc.QuotaPeakNonPagedPoolUsage );
        printf( "\tQuotaNonPagedPoolUsage: 0x%08X\n", 
                  pmc.QuotaNonPagedPoolUsage );
        printf( "\tPagefileUsage: 0x%08X\n", pmc.PagefileUsage ); 
        printf( "\tPeakPagefileUsage: 0x%08X\n", 
                  pmc.PeakPagefileUsage );
    }

    CloseHandle( hProcess );
}

int main( void )
{
    // Get the list of process identifiers.

    DWORD aProcesses[1024], cbNeeded, cProcesses;
    unsigned int i;

    if ( !EnumProcesses( aProcesses, sizeof(aProcesses), &cbNeeded ) )
    {
        return 1;
    }

    // Calculate how many process identifiers were returned.

    cProcesses = cbNeeded / sizeof(DWORD);

    // Print the memory usage for each process

    for ( i = 0; i < cProcesses; i++ )
    {
        PrintMemoryInfo( aProcesses[i] );
    }

    return 0;
}

Fungsi utama mendapatkan daftar proses melalui fungsi EnumProcesses. Untuk setiap proses, main memanggil fungsi PrintMemoryInfo, sambil meneruskan pengenal proses. PrintMemoryInfo pada gilirannya memanggil fungsi OpenProcess untuk mendapatkan handle proses. Jika OpenProcess gagal, output hanya menunjukkan pengidentifikasi proses. Misalnya, OpenProcess gagal untuk proses Idle dan CSRSS karena pembatasan aksesnya mencegah kode tingkat pengguna membukanya. Terakhir, PrintMemoryInfo memanggil fungsiGetProcessMemoryInfo untuk mendapatkan informasi penggunaan memori.