Memory usage per process in C++

Code:

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

void PrintMemoryInfo( DWORD processID )
{
    HANDLE hProcess;
    PROCESS_MEMORY_COUNTERS pmc;
    printf( "\nProcess ID: %u\n", processID );
    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 )
{
    DWORD aProcesses[1024], cbNeeded, cProcesses;
    unsigned int i;
    if ( !EnumProcesses( aProcesses, sizeof(aProcesses), &cbNeeded ) )
    {
        return 1;
    }
    cProcesses = cbNeeded / sizeof(DWORD);
    for ( i = 0; i < cProcesses; i++ )
    {
        PrintMemoryInfo( aProcesses[i] );
    }
    return 0;
}

Compile with g++:

g++ Source1.cpp -lpsapi -o s1

Save output to a text file:

g++ Source1.cpp -lpsapi -o s1

Output stored in text file:

Process ID: 0

Process ID: 4

Process ID: 420

Process ID: 600

Process ID: 656

Process ID: 664

Process ID: 704

Process ID: 756

Process ID: 764

Process ID: 772

Process ID: 872

Process ID: 952

Process ID: 304

Process ID: 520

Process ID: 568

Process ID: 592

Process ID: 1188

Process ID: 1284

Process ID: 1388

Process ID: 1540

Process ID: 1568

Process ID: 1600

Process ID: 1784

Process ID: 1856

Process ID: 1880

Process ID: 1912

Process ID: 1980

Process ID: 1140

Process ID: 1620

Process ID: 1812

Process ID: 1804

Process ID: 1988

Process ID: 2156

Process ID: 2260
    PageFaultCount: 0x0000B2DF
    PeakWorkingSetSize: 0x01335000
    WorkingSetSize: 0x0103A000
    QuotaPeakPagedPoolUsage: 0x0003B0C0
    QuotaPagedPoolUsage: 0x00039410
    QuotaPeakNonPagedPoolUsage: 0x0000A560
    QuotaNonPagedPoolUsage: 0x00008FD8
    PagefileUsage: 0x00EA2000
    PeakPagefileUsage: 0x00FA4000

Process ID: 2400
    PageFaultCount: 0x00000BFA
    PeakWorkingSetSize: 0x00AB5000
    WorkingSetSize: 0x004B9000
    QuotaPeakPagedPoolUsage: 0x000206A0
    QuotaPagedPoolUsage: 0x0001FA90
    QuotaPeakNonPagedPoolUsage: 0x000026A8
    QuotaNonPagedPoolUsage: 0x00001EB8
    PagefileUsage: 0x00211000
    PeakPagefileUsage: 0x006BC000

Process ID: 2428
    PageFaultCount: 0x0001BC29
    PeakWorkingSetSize: 0x05967000
    WorkingSetSize: 0x043F1000
    QuotaPeakPagedPoolUsage: 0x000BCF08
    QuotaPagedPoolUsage: 0x0008BD28
    QuotaPeakNonPagedPoolUsage: 0x0001A9F8
    QuotaNonPagedPoolUsage: 0x000162F8
    PagefileUsage: 0x03F4B000
    PeakPagefileUsage: 0x0501B000

Process ID: 2448

Process ID: 2744

Process ID: 2752

Process ID: 2864

Process ID: 2896

Process ID: 2956
    PageFaultCount: 0x00000FAD
    PeakWorkingSetSize: 0x009BE000
    WorkingSetSize: 0x00703000
    QuotaPeakPagedPoolUsage: 0x00029D08
    QuotaPagedPoolUsage: 0x00027B18
    QuotaPeakNonPagedPoolUsage: 0x00003A10
    QuotaNonPagedPoolUsage: 0x00002E70
    PagefileUsage: 0x00336000
    PeakPagefileUsage: 0x00376000

Process ID: 2980
    PageFaultCount: 0x0000033B
    PeakWorkingSetSize: 0x00316000
    WorkingSetSize: 0x00284000
    QuotaPeakPagedPoolUsage: 0x00014678
    QuotaPagedPoolUsage: 0x00014678
    QuotaPeakNonPagedPoolUsage: 0x00001E78
    QuotaNonPagedPoolUsage: 0x00001958
    PagefileUsage: 0x000F0000
    PeakPagefileUsage: 0x000F0000

Process ID: 3004
    PageFaultCount: 0x00000784
    PeakWorkingSetSize: 0x005B2000
    WorkingSetSize: 0x003F9000
    QuotaPeakPagedPoolUsage: 0x00021C68
    QuotaPagedPoolUsage: 0x000217D8
    QuotaPeakNonPagedPoolUsage: 0x00002500
    QuotaNonPagedPoolUsage: 0x00001EF0
    PagefileUsage: 0x00287000
    PeakPagefileUsage: 0x002A3000

Process ID: 3044
    PageFaultCount: 0x000004C9
    PeakWorkingSetSize: 0x004B7000
    WorkingSetSize: 0x0034D000
    QuotaPeakPagedPoolUsage: 0x00019470
    QuotaPagedPoolUsage: 0x000193F0
    QuotaPeakNonPagedPoolUsage: 0x00001D80
    QuotaNonPagedPoolUsage: 0x00001860
    PagefileUsage: 0x001DA000
    PeakPagefileUsage: 0x001F0000

Process ID: 3060
    PageFaultCount: 0x0000A58C
    PeakWorkingSetSize: 0x05FD1000
    WorkingSetSize: 0x04E68000
    QuotaPeakPagedPoolUsage: 0x000FE5D0
    QuotaPagedPoolUsage: 0x000FD6C0
    QuotaPeakNonPagedPoolUsage: 0x0001B91C
    QuotaNonPagedPoolUsage: 0x00012DE8
    PagefileUsage: 0x066FA000
    PeakPagefileUsage: 0x066FD000

Process ID: 2100
    PageFaultCount: 0x00001921
    PeakWorkingSetSize: 0x014ED000
    WorkingSetSize: 0x00BAB000
    QuotaPeakPagedPoolUsage: 0x0003B4A0
    QuotaPagedPoolUsage: 0x0003AC48
    QuotaPeakNonPagedPoolUsage: 0x000065A8
    QuotaNonPagedPoolUsage: 0x000055F8
    PagefileUsage: 0x00D3C000
    PeakPagefileUsage: 0x00E3F000

Process ID: 2324
    PageFaultCount: 0x0000063D
    PeakWorkingSetSize: 0x0057E000
    WorkingSetSize: 0x003EC000
    QuotaPeakPagedPoolUsage: 0x00020D98
    QuotaPagedPoolUsage: 0x00020908
    QuotaPeakNonPagedPoolUsage: 0x00002B88
    QuotaNonPagedPoolUsage: 0x00001FE8
    PagefileUsage: 0x00259000
    PeakPagefileUsage: 0x002FC000

Process ID: 2460
    PageFaultCount: 0x000004FE
    PeakWorkingSetSize: 0x004EA000
    WorkingSetSize: 0x003DC000
    QuotaPeakPagedPoolUsage: 0x0001F8F8
    QuotaPagedPoolUsage: 0x0001F468
    QuotaPeakNonPagedPoolUsage: 0x00001EE8
    QuotaNonPagedPoolUsage: 0x000018D8
    PagefileUsage: 0x001B4000
    PeakPagefileUsage: 0x001DE000

Process ID: 2568
    PageFaultCount: 0x000037A6
    PeakWorkingSetSize: 0x02CA0000
    WorkingSetSize: 0x0210B000
    QuotaPeakPagedPoolUsage: 0x0002BFE8
    QuotaPagedPoolUsage: 0x0002B5E8
    QuotaPeakNonPagedPoolUsage: 0x0000A060
    QuotaNonPagedPoolUsage: 0x00009998
    PagefileUsage: 0x02D52000
    PeakPagefileUsage: 0x02E68000

Process ID: 2312

Process ID: 2792
    PageFaultCount: 0x00000D97
    PeakWorkingSetSize: 0x008ED000
    WorkingSetSize: 0x00399000
    QuotaPeakPagedPoolUsage: 0x00029BD0
    QuotaPagedPoolUsage: 0x000293C0
    QuotaPeakNonPagedPoolUsage: 0x000047F0
    QuotaNonPagedPoolUsage: 0x00003E98
    PagefileUsage: 0x002F1000
    PeakPagefileUsage: 0x00313000

Process ID: 4088
    PageFaultCount: 0x000054DB
    PeakWorkingSetSize: 0x0124B000
    WorkingSetSize: 0x002F4000
    QuotaPeakPagedPoolUsage: 0x000377A0
    QuotaPagedPoolUsage: 0x00037190
    QuotaPeakNonPagedPoolUsage: 0x00009010
    QuotaNonPagedPoolUsage: 0x00008AF0
    PagefileUsage: 0x00B47000
    PeakPagefileUsage: 0x00BCE000

Process ID: 2720

Process ID: 3744
    PageFaultCount: 0x00023E63
    PeakWorkingSetSize: 0x0C0CE000
    WorkingSetSize: 0x06522000
    QuotaPeakPagedPoolUsage: 0x0010DBB0
    QuotaPagedPoolUsage: 0x001085E0
    QuotaPeakNonPagedPoolUsage: 0x0001ACF0
    QuotaNonPagedPoolUsage: 0x00014100
    PagefileUsage: 0x05EBD000
    PeakPagefileUsage: 0x27640000

Process ID: 3508

Process ID: 948

Process ID: 864

Process ID: 4188

Process ID: 4212

Process ID: 4300

Process ID: 4368

Process ID: 4444

Process ID: 4532

Process ID: 4552

Process ID: 4572

Process ID: 4864

Process ID: 3244

Process ID: 5156

Process ID: 5388

Process ID: 5536

Process ID: 5620

Process ID: 6584
    PageFaultCount: 0x000019FF
    PeakWorkingSetSize: 0x016AE000
    WorkingSetSize: 0x016A8000
    QuotaPeakPagedPoolUsage: 0x0009C118
    QuotaPagedPoolUsage: 0x0009B628
    QuotaPeakNonPagedPoolUsage: 0x00009F18
    QuotaNonPagedPoolUsage: 0x00009130
    PagefileUsage: 0x009A1000
    PeakPagefileUsage: 0x009E9000

Process ID: 6944

Process ID: 7024

Process ID: 7088

Process ID: 5692

Process ID: 7136

Process ID: 5572
    PageFaultCount: 0x00544F2F
    PeakWorkingSetSize: 0x19185000
    WorkingSetSize: 0x16724000
    QuotaPeakPagedPoolUsage: 0x00087008
    QuotaPagedPoolUsage: 0x0006EE68
    QuotaPeakNonPagedPoolUsage: 0x0005C99C
    QuotaNonPagedPoolUsage: 0x00019030
    PagefileUsage: 0x164C6000
    PeakPagefileUsage: 0x196DC000

Process ID: 5824
    PageFaultCount: 0x000030EC
    PeakWorkingSetSize: 0x029E2000
    WorkingSetSize: 0x02938000
    QuotaPeakPagedPoolUsage: 0x00076E20
    QuotaPagedPoolUsage: 0x000756F0
    QuotaPeakNonPagedPoolUsage: 0x00013C5C
    QuotaNonPagedPoolUsage: 0x00013644
    PagefileUsage: 0x01D75000
    PeakPagefileUsage: 0x02046000

Process ID: 5548
    PageFaultCount: 0x000027C5
    PeakWorkingSetSize: 0x01C92000
    WorkingSetSize: 0x01BA9000
    QuotaPeakPagedPoolUsage: 0x00042858
    QuotaPagedPoolUsage: 0x00041CB8
    QuotaPeakNonPagedPoolUsage: 0x00024A94
    QuotaNonPagedPoolUsage: 0x0000402C
    PagefileUsage: 0x0158B000
    PeakPagefileUsage: 0x01718000

Process ID: 7040
    PageFaultCount: 0x000003AC
    PeakWorkingSetSize: 0x003A7000
    WorkingSetSize: 0x003A0000
    QuotaPeakPagedPoolUsage: 0x000177A8
    QuotaPagedPoolUsage: 0x00017588
    QuotaPeakNonPagedPoolUsage: 0x000012C0
    QuotaNonPagedPoolUsage: 0x000012C0
    PagefileUsage: 0x00170000
    PeakPagefileUsage: 0x00170000

Process ID: 4000
    PageFaultCount: 0x0000088A
    PeakWorkingSetSize: 0x004B8000
    WorkingSetSize: 0x00467000
    QuotaPeakPagedPoolUsage: 0x00006850
    QuotaPagedPoolUsage: 0x00006830
    QuotaPeakNonPagedPoolUsage: 0x00001B40
    QuotaNonPagedPoolUsage: 0x00001688
    PagefileUsage: 0x00225000
    PeakPagefileUsage: 0x00298000

Process ID: 6556
    PageFaultCount: 0x000071F5
    PeakWorkingSetSize: 0x05C29000
    WorkingSetSize: 0x02EDB000
    QuotaPeakPagedPoolUsage: 0x0004D730
    QuotaPagedPoolUsage: 0x000436B0
    QuotaPeakNonPagedPoolUsage: 0x000080C8
    QuotaNonPagedPoolUsage: 0x00005F30
    PagefileUsage: 0x02399000
    PeakPagefileUsage: 0x050E1000

Process ID: 7056
    PageFaultCount: 0x00000FBC
    PeakWorkingSetSize: 0x00EE0000
    WorkingSetSize: 0x00EAB000
    QuotaPeakPagedPoolUsage: 0x000361C8
    QuotaPagedPoolUsage: 0x00036158
    QuotaPeakNonPagedPoolUsage: 0x00005048
    QuotaNonPagedPoolUsage: 0x00004B58
    PagefileUsage: 0x0096A000
    PeakPagefileUsage: 0x009AD000

Process ID: 2740
    PageFaultCount: 0x0000FB50
    PeakWorkingSetSize: 0x08D09000
    WorkingSetSize: 0x08630000
    QuotaPeakPagedPoolUsage: 0x000C5358
    QuotaPagedPoolUsage: 0x000C04C8
    QuotaPeakNonPagedPoolUsage: 0x000155A4
    QuotaNonPagedPoolUsage: 0x000135A4
    PagefileUsage: 0x05BCB000
    PeakPagefileUsage: 0x070D6000

Process ID: 4196
    PageFaultCount: 0x00004253
    PeakWorkingSetSize: 0x02477000
    WorkingSetSize: 0x022EE000
    QuotaPeakPagedPoolUsage: 0x00036DB0
    QuotaPagedPoolUsage: 0x00036620
    QuotaPeakNonPagedPoolUsage: 0x00017960
    QuotaNonPagedPoolUsage: 0x000172D0
    PagefileUsage: 0x03406000
    PeakPagefileUsage: 0x03538000

Process ID: 5896

Process ID: 2680
    PageFaultCount: 0x0000034D
    PeakWorkingSetSize: 0x00318000
    WorkingSetSize: 0x00317000
    QuotaPeakPagedPoolUsage: 0x00016968
    QuotaPagedPoolUsage: 0x000162F8
    QuotaPeakNonPagedPoolUsage: 0x00001478
    QuotaNonPagedPoolUsage: 0x00001248
    PagefileUsage: 0x00241000
    PeakPagefileUsage: 0x0024E000

Process ID: 3400
    PageFaultCount: 0x000005C9
    PeakWorkingSetSize: 0x00571000
    WorkingSetSize: 0x0056F000
    QuotaPeakPagedPoolUsage: 0x00020400
    QuotaPagedPoolUsage: 0x0001FC80
    QuotaPeakNonPagedPoolUsage: 0x00001B30
    QuotaNonPagedPoolUsage: 0x00001A40
    PagefileUsage: 0x001D0000
    PeakPagefileUsage: 0x001D0000

Process ID: 6856

Process ID: 192
    PageFaultCount: 0x00000835
    PeakWorkingSetSize: 0x006C0000
    WorkingSetSize: 0x006BD000
    QuotaPeakPagedPoolUsage: 0x0001DA00
    QuotaPagedPoolUsage: 0x0001D5C0
    QuotaPeakNonPagedPoolUsage: 0x00002290
    QuotaNonPagedPoolUsage: 0x00002120
    PagefileUsage: 0x002EF000
    PeakPagefileUsage: 0x002FA000

Process ID: 6212

Process ID: 5268
    PageFaultCount: 0x00000582
    PeakWorkingSetSize: 0x0055D000
    WorkingSetSize: 0x0055D000
    QuotaPeakPagedPoolUsage: 0x00014D28
    QuotaPagedPoolUsage: 0x00014CF8
    QuotaPeakNonPagedPoolUsage: 0x000021F8
    QuotaNonPagedPoolUsage: 0x000021F8
    PagefileUsage: 0x00242000
    PeakPagefileUsage: 0x00242000

Process ID: 6308
    PageFaultCount: 0x000003C4
    PeakWorkingSetSize: 0x003BE000
    WorkingSetSize: 0x003BE000
    QuotaPeakPagedPoolUsage: 0x00017DE0
    QuotaPagedPoolUsage: 0x00017588
    QuotaPeakNonPagedPoolUsage: 0x000012C0
    QuotaNonPagedPoolUsage: 0x000012C0
    PagefileUsage: 0x00173000
    PeakPagefileUsage: 0x00252000

Process ID: 1692
    PageFaultCount: 0x000001C0
    PeakWorkingSetSize: 0x001C1000
    WorkingSetSize: 0x001C1000
    QuotaPeakPagedPoolUsage: 0x00003DC0
    QuotaPagedPoolUsage: 0x00003DC0
    QuotaPeakNonPagedPoolUsage: 0x000009D8
    QuotaNonPagedPoolUsage: 0x000009D8
    PagefileUsage: 0x000CB000
    PeakPagefileUsage: 0x000CB000

This C++ snippet reports the memory used by one process on Windows. It opens the process by its ID and reads a PROCESS_MEMORY_COUNTERS structure through the PSAPI library, which exposes working set and page file usage.

Per process figures help with spotting leaks or comparing the footprint of different builds. The code is Windows specific because it uses windows.h and psapi; on Linux you would read /proc//status instead.