public unsafe void Test()
{
var pool = new DynamicMemoryPool();
uint blocksize = 234401;
var pblock = (byte *)pool.Alloc(blocksize);
var stream = new MemoryViewStream();
stream.Attach(pblock, blocksize);
var data = new byte[blocksize];
for (var i = 0; i < data.Length; i++)
{
data[i] = (byte)i;
}
using (var writer = new BinaryWriter(stream, Encoding.UTF8, true))
{
writer.Write(data, 0, data.Length);
}
if (stream.Position != stream.Length)
{
throw new Exception("Invalid position: " + stream.Position);
}
stream.Seek(0, SeekOrigin.Begin);
if (stream.Position != 0)
{
throw new Exception("Invalid position: " + stream.Position);
}
using (var reader = new BinaryReader(stream, Encoding.UTF8, true))
{
for (var i = 0; i < data.Length; i++)
{
//if (data[i] != *(pblock + i))
if (data[i] != reader.ReadByte())
{
throw new Exception("Failed at " + i);
}
}
}
return;
if (stream.Position != stream.Length)
{
throw new Exception("Invalid position: " + stream.Position);
}
stream.Position = 0;
}
/*
* Main goals:
* 1. No copies, ever. States are deposited directly to, and read directly from, one giant ring buffer.
* As a consequence, there is no multi-threading because there is nothing to thread.
* 2. Support for arbitrary and changeable state sizes. Frequency is calculated dynamically.
* 3. No delta compression. Keep it simple. If there are cores that benefit heavily from delta compression, we should
* maintain a separate rewinder alongside this one that is customized for those cores.
*/
public ZwinderBuffer(IRewindSettings settings)
{
if (settings == null)
{
throw new ArgumentException("ZwinderBuffer's settings cannot be null.");
}
long targetSize = settings.BufferSize * 1024 * 1024;
if (settings.TargetFrameLength < 1)
{
throw new ArgumentOutOfRangeException(nameof(settings.TargetFrameLength));
}
Size = 1L << (int)Math.Floor(Math.Log(targetSize, 2));
_sizeMask = Size - 1;
_backingStoreType = settings.BackingStore;
switch (settings.BackingStore)
{
case IRewindSettings.BackingStoreType.Memory:
{
var buffer = new MemoryBlock((ulong)Size);
buffer.Protect(buffer.Start, buffer.Size, MemoryBlock.Protection.RW);
_disposables.Add(buffer);
_backingStore = new MemoryViewStream(true, true, (long)buffer.Start, (long)buffer.Size);
_disposables.Add(_backingStore);
break;
}
case IRewindSettings.BackingStoreType.TempFile:
{
var filename = TempFileManager.GetTempFilename("ZwinderBuffer");
var filestream = new FileStream(filename, FileMode.Create, FileAccess.ReadWrite, FileShare.None, 4096, FileOptions.DeleteOnClose);
filestream.SetLength(Size);
_backingStore = filestream;
_disposables.Add(filestream);
break;
}
default:
throw new ArgumentException("Unsupported store type for ZwinderBuffer.");
}
if (settings.UseFixedRewindInterval)
{
_fixedRewindInterval = true;
_targetRewindInterval = settings.TargetRewindInterval;
}
else
{
_fixedRewindInterval = false;
_targetFrameLength = settings.TargetFrameLength;
}
_allowOutOfOrderStates = settings.AllowOutOfOrderStates;
_states = new StateInfo[STATEMASK + 1];
_useCompression = settings.UseCompression;
}
public unsafe void Test()
{
var pool = new DynamicMemoryPool();
uint blocksize = 234401;
var pblock = (byte*)pool.Alloc(blocksize);
var stream = new MemoryViewStream();
stream.Attach(pblock, blocksize);
var data = new byte[blocksize];
for (var i = 0; i < data.Length; i++)
{
data[i] = (byte)i;
}
using (var writer = new BinaryWriter(stream, Encoding.UTF8, true))
{
writer.Write(data, 0, data.Length);
}
if (stream.Position != stream.Length)
{
throw new Exception("Invalid position: " + stream.Position);
}
stream.Seek(0, SeekOrigin.Begin);
if (stream.Position != 0)
{
throw new Exception("Invalid position: " + stream.Position);
}
using (var reader = new BinaryReader(stream, Encoding.UTF8, true))
{
for (var i = 0; i < data.Length; i++)
{
//if (data[i] != *(pblock + i))
if (data[i] != reader.ReadByte())
{
throw new Exception("Failed at " + i);
}
}
}
return;
if (stream.Position != stream.Length)
{
throw new Exception("Invalid position: " + stream.Position);
}
stream.Position = 0;
}
