Retrieves information about the system's current usage of both physical and virtual memory.
Syntax
BOOL WINAPI GlobalMemoryStatusEx(
__inout LPMEMORYSTATUSEX lpBuffer
);
Parameters
- lpBuffer [in, out]
-
A pointer to a
MEMORYSTATUSEX structure that receives information about current memory availability.
Return Value
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call
GetLastError.
Remarks
You can use the
GlobalMemoryStatusEx function to determine how much memory your application can allocate without severely impacting other applications.
The information returned by the
GlobalMemoryStatusEx function is volatile. There is no guarantee that two sequential calls to this function will return the same information.
The ullAvailPhys member of the MEMORYSTATUSEX structure at lpBuffer includes memory for all NUMA nodes.
Examples
The following code shows a simple use of the
GlobalMemoryStatusEx function.
// Sample output:
// There is 51 percent of memory in use.
// There are 2029968 total Kbytes of physical memory.
// There are 987388 free Kbytes of physical memory.
// There are 3884620 total Kbytes of paging file.
// There are 2799776 free Kbytes of paging file.
// There are 2097024 total Kbytes of virtual memory.
// There are 2084876 free Kbytes of virtual memory.
// There are 0 free Kbytes of extended memory.
#include <windows.h>
#include <stdio.h>
// Use to convert bytes to KB
#define DIV 1024
// Specify the width of the field in which to print the numbers.
// The asterisk in the format specifier "%*I64d" takes an integer
// argument and uses it to pad and right justify the number.
#define WIDTH 7
void main(int argc, char *argv[])
{
MEMORYSTATUSEX statex;
statex.dwLength = sizeof (statex);
GlobalMemoryStatusEx (&statex);
printf ("There is %*ld percent of memory in use.\n",
WIDTH, statex.dwMemoryLoad);
printf ("There are %*I64d total Kbytes of physical memory.\n",
WIDTH, statex.ullTotalPhys/DIV);
printf ("There are %*I64d free Kbytes of physical memory.\n",
WIDTH, statex.ullAvailPhys/DIV);
printf ("There are %*I64d total Kbytes of paging file.\n",
WIDTH, statex.ullTotalPageFile/DIV);
printf ("There are %*I64d free Kbytes of paging file.\n",
WIDTH, statex.ullAvailPageFile/DIV);
printf ("There are %*I64d total Kbytes of virtual memory.\n",
WIDTH, statex.ullTotalVirtual/DIV);
printf ("There are %*I64d free Kbytes of virtual memory.\n",
WIDTH, statex.ullAvailVirtual/DIV);
// Show the amount of extended memory available.
printf ("There are %*I64d free Kbytes of extended memory.\n",
WIDTH, statex.ullAvailExtendedVirtual/DIV);
}
Requirements
| Minimum supported client | Windows 2000 Professional |
|---|
| Minimum supported server | Windows 2000 Server |
|---|
| Header | Winbase.h (include Windows.h) |
|---|
| Library | Kernel32.lib |
|---|
| DLL | Kernel32.dll |
|---|
See Also
- Memory
Management Functions
- Memory Performance Information
- MEMORYSTATUSEX
- Virtual Address Space and Physical Storage
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Build date: 9/17/2009