Constantin: Thanks! That link has a command-line EXE which does the testing I was looking for.
I also found a link off that page to a more interesting article (in Word and PDF) on this page: Sequential File Programming Patterns and Performance with .NET
In this article, it talks about Un-buffered File Performance (iow, no read/write caching -- just raw disk performance.)
Quoted directly from the article:
There is no simple way to disable FileStream buffering in the V2 .NET framework. One must invoke the Windows file system directly to obtain an un-buffered file handle and then ‘wrap’ the result in a FileStream as follows in C#:
[DllImport("kernel32", SetLastError=true)]
static extern unsafe SafeFileHandle CreateFile(
string FileName, // file name
uint DesiredAccess, // access mode
uint ShareMode, // share mode
IntPtr SecurityAttributes, // Security Attr
uint CreationDisposition, // how to create
uint FlagsAndAttributes, // file attributes
SafeFileHandle hTemplate // template file
);
SafeFileHandle handle = CreateFile(FileName,
FileAccess.Read,
FileShare.None,
IntPtr.Zero,
FileMode.Open,
FILE_FLAG_NO_BUFFERING,
null);
FileStream stream = new FileStream(handle,
FileAccess.Read,
true,
4096);
Calling CreateFile() with the FILE_FLAG_NO_BUFFERING flag tells the file system to bypass all software memory caching for the file. The ‘true’ value passed as the third argument to the FileStream constructor indicates that the stream should take ownership of the file handle, meaning that the file handle will automatically be closed when the stream is closed. After this hocus-pocus, the un-buffered file stream is read and written in the same way as any other.
