struct HEAP_TAG_ENTRY

typedef struct _HEAP_TAG_ENTRY
{
     ULONG Allocs;
     ULONG Frees;
     ULONG Size;
     WORD TagIndex;
     WORD CreatorBackTraceIndex;
     WCHAR TagName[24];
} HEAP_TAG_ENTRY, *PHEAP_TAG_ENTRY;

Windows Vista Kernel Structures