NtSetSystemInformation(SystemFileCacheInformation) on 64-bit Windows

Hi,

does anyone know the structure necessary to pass data
to NtSetSystemInformation with SystemFileCacheInformation ?

I tried to port Mark’s Russinovich’s CACHESET
utility to Win64 and I found that the structure is
different.

From the memory block filled by NtQuerySystemInformation,
the structure seems to be

typedef struct _SYSTEM_FILECACHE_INFORMATION
{
ULONG_PTR CurrentSize;
ULONG_PTR PeakSize;
ULONG PageFaultCount;

// Nothing more is returned

}SYSTEM_FILECACHE_INFORMATION;

It seems strange to me, because the source structure
(MMSUPPORT MmSystemCacheWs) has not changed
with moving to 64-bit. On Win32, the NtQuerySystemInfo
copies the members of filecache struct from MmSystemCacheWs,
if MmSystemCacheWs remained the same, then the structure should
also remain the same.

L.