KeQueryMaximumGroupCount function (wdm.h)
The KeQueryMaximumGroupCount routine returns the maximum number of groups in a multiprocessor system.
Syntax
USHORT KeQueryMaximumGroupCount();
Return value
KeQueryMaximumGroupCount returns the maximum number of groups.
Remarks
The value that is returned by KeQueryMaximumGroupCount remains constant during runtime. This value depends on the hardware configuration of the multiprocessor system, but it can never exceed a fixed limit that is set by the Windows operating system.
In Windows 7, the maximum number of groups in a multiprocessor system is four, but this value might change in future versions of Windows. The safest way to determine the maximum number of groups in Windows 7 or a later versions of the Windows operating system is to call KeQueryMaximumGroupCount. Kernel-mode drivers that call KeQueryMaximumGroupCount will not require code changes if the formula that is used to calculate the maximum number of groups changes in a future version of Windows.
To obtain the number of active groups in a multiprocessor system, call the KeQueryActiveGroupCount routine.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Available in Windows 7 and later versions of Windows. |
| Target Platform | Universal |
| Header | wdm.h (include Wdm.h, Ntddk.h, Ntifs.h) |
| Library | NtosKrnl.lib |
| DLL | NtosKrnl.exe |
| IRQL | Any level |