public static SharedBuffer CreateBuffer(Guid id, Type elementType, long bufferSize)
{
var sb = new SharedBuffer();
sb.Id = id;
sb.ElementTypeString = elementType.FullName;
sb.ElementSize = Marshal.SizeOf(elementType);
sb.ElementCount = bufferSize;
if (_blockPath != string.Empty)
{
var fileStream = System.IO.File.Create(string.Format(@"{0}\{1}", _blockPath, id.ToString()),
(int)(bufferSize * sb.ElementSize), System.IO.FileOptions.DeleteOnClose);
var mmf = MemoryMappedFile.CreateFromFile(fileStream, id.ToString(),
(int)(bufferSize * sb.ElementSize),
MemoryMappedFileAccess.ReadWrite, null, System.IO.HandleInheritability.None, false);
_cacheBuffers.TryAdd(id, sb);
_cacheMmfs.TryAdd(id, mmf);
_cacheFileStreams.TryAdd(id, fileStream);
}
else
{
var mmf = MemoryMappedFile.CreateNew(id.ToString(),
bufferSize * sb.ElementSize);
_cacheBuffers.TryAdd(id, sb);
_cacheMmfs.TryAdd(id, mmf);
}
return sb;
}
/// <summary>
///
/// </summary>
/// <param name="sb"></param>
public void PrefetchBuffer(SharedBuffer sb)
{
if ((!_sbStack.Any(sbOther => sbOther.Id.CompareTo(sb.Id) == 0))
&& (!_sbDone.Any(sbOther => sbOther.Id.CompareTo(sb.Id) == 0)))
_sbStack.Push(sb);
if (_sbPrefetchTask == null
|| _sbPrefetchTask.Status != System.Threading.Tasks.TaskStatus.Running)
{
Action prefetchAction = () =>
{
try
{
while (true)
{
SharedBuffer sbLocal;
if (_sbStack.TryPop(out sbLocal))
{
//#if SLOW_POKE
// var handle = sbLocal.GetHandle();
// const long STEP_SIZE = 4096;
// long numSteps = (long)handle.ByteLength / STEP_SIZE;
// System.Threading.Tasks.Parallel.For(0, numSteps,
// at => handle.Read<byte>((ulong)(at * STEP_SIZE)));
// sbLocal.ReleaseHandle();
//#else
// BufferRepository.ReadFile(sbLocal.Id);
//#endif
_sbDone.Add(sbLocal);
}
}
}
finally
{
System.Console.WriteLine("Exiting prefetch...");
}
};
_sbPrefetchTask = new System.Threading.Tasks.Task(prefetchAction);
_sbPrefetchTask.Start();
}
}
