/// <summary>Verify that du returns expected used space for a file.</summary>
/// <remarks>
/// Verify that du returns expected used space for a file.
/// We assume here that if a file system crates a file of size
/// that is a multiple of the block size in this file system,
/// then the used size for the file will be exactly that size.
/// This is true for most file systems.
/// </remarks>
/// <exception cref="System.IO.IOException"/>
/// <exception cref="System.Exception"/>
public virtual void TestDU()
{
int writtenSize = 32 * 1024;
// writing 32K
// Allow for extra 4K on-disk slack for local file systems
// that may store additional file metadata (eg ext attrs).
int slack = 4 * 1024;
FilePath file = new FilePath(DuDir, "data");
CreateFile(file, writtenSize);
Thread.Sleep(5000);
// let the metadata updater catch up
DU du = new DU(file, 10000);
du.Start();
long duSize = du.GetUsed();
du.Shutdown();
Assert.True("Invalid on-disk size", duSize >= writtenSize && writtenSize
<= (duSize + slack));
//test with 0 interval, will not launch thread
du = new DU(file, 0);
du.Start();
duSize = du.GetUsed();
du.Shutdown();
Assert.True("Invalid on-disk size", duSize >= writtenSize && writtenSize
<= (duSize + slack));
//test without launching thread
du = new DU(file, 10000);
duSize = du.GetUsed();
Assert.True("Invalid on-disk size", duSize >= writtenSize && writtenSize
<= (duSize + slack));
}
