Practical Usage of Virtual Memory

Question

I have used the code

MEMORYSTATUSEX memInfo;
memInfo.dwLength = sizeof(MEMORYSTATUSEX);
GlobalMemoryStatusEx(&memInfo);
DWORDLONG totalVirtualMem = memInfo.ullTotalPageFile;
DWORDLONG virtualMemUsed = memInfo.ullTotalPageFile - memInfo.ullAvailPageFile;
DWORDLONG totalPhysMem = memInfo.ullTotalPhys;

provided at here

Output is like: 2.3GB.

totalVirtualMem = 8.5 Gb
virtualMemUsed  = 2.3 Gb
totalPhysMem    = 4   Gb

Does this means that my program requires 2.3Gb of memory? Could you also comment on total virtual memory and RAM? Also I was not able to run this code:

PROCESS_MEMORY_COUNTERS_EX pmc;
GetProcessMemoryInfo(GetCurrentProcess(), &pmc, sizeof(pmc));
SIZE_T virtualMemUsedByMe = pmc.PrivateUsage;

as it gives error as,

error C2664: 'GetProcessMemoryInfo' : cannot convert parameter 2 from 'PROCESS_MEMORY_COUNTERS_EX *' to 'PPROCESS_MEMORY_COUNTERS'

Answer 1

I stumbled upon exactly the same Problem and found out that a simple type cast solved it for me.

PROCESS_MEMORY_COUNTERS_EX pmc;
GetProcessMemoryInfo(GetCurrentProcess(), (PROCESS_MEMORY_COUNTERS*)&pmc, sizeof(pmc));
SIZE_T virtualMemUsedByMe = pmc.PrivateUsage;

The solution is also described here (msdn: Question about GetProcessMemoryInfo).