Use system.buffers for our reader/writer

src/Microsoft.AspNet.Mvc.Core/DependencyInjection/MvcCoreServiceCollectionExtensions.cs

@@ -2,8 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using Microsoft.AspNet.Http;
+using System.Buffers;
-using Microsoft.AspNet.Http.Internal;
 using Microsoft.AspNet.Mvc;
 using Microsoft.AspNet.Mvc.Abstractions;
 using Microsoft.AspNet.Mvc.ActionConstraints;
@@ -18,7 +17,6 @@ using Microsoft.AspNet.Mvc.ModelBinding.Validation;
 using Microsoft.AspNet.Mvc.Routing;
 using Microsoft.AspNet.Routing;
 using Microsoft.Extensions.DependencyInjection.Extensions;
-using Microsoft.Extensions.MemoryPool;
 using Microsoft.Extensions.OptionsModel;
 using Microsoft.Extensions.PlatformAbstractions;
 
@@ -144,8 +142,8 @@ namespace Microsoft.Extensions.DependencyInjection
             services.TryAddSingleton<IUrlHelperFactory, UrlHelperFactory>();
             services.TryAddSingleton<IHttpRequestStreamReaderFactory, MemoryPoolHttpRequestStreamReaderFactory>();
             services.TryAddSingleton<IHttpResponseStreamWriterFactory, MemoryPoolHttpResponseStreamWriterFactory>();
-            services.TryAddSingleton<IArraySegmentPool<byte>, DefaultArraySegmentPool<byte>>();
+            services.TryAddSingleton(ArrayPool<byte>.Shared);
-            services.TryAddSingleton<IArraySegmentPool<char>, DefaultArraySegmentPool<char>>();
+            services.TryAddSingleton(ArrayPool<char>.Shared);
             services.TryAddSingleton<ObjectResultExecutor>();
         }
 

src/Microsoft.AspNet.Mvc.Core/HttpResponseStreamWriter.cs

@@ -2,11 +2,11 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Buffers;
 using System.IO;
 using System.Text;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Mvc.Core;
-using Microsoft.Extensions.MemoryPool;
 
 namespace Microsoft.AspNet.Mvc
 {
@@ -23,13 +23,15 @@ namespace Microsoft.AspNet.Mvc
         /// </summary>
         public const int DefaultBufferSize = 1024;
 
-        private readonly Stream _stream;
+        private Stream _stream;
-        private Encoder _encoder;
+        private readonly Encoder _encoder;
-        private LeasedArraySegment<byte> _leasedByteBuffer;
+        private readonly ArrayPool<byte> _bytePool;
-        private LeasedArraySegment<char> _leasedCharBuffer;
+        private readonly ArrayPool<char> _charPool;
-        private ArraySegment<byte> _byteBuffer;
+        private readonly int _charBufferSize;
-        private ArraySegment<char> _charBuffer;
+
-        private int _charBufferSize;
+        private byte[] _byteBuffer;
+        private char[] _charBuffer;
+
         private int _charBufferCount;
 
         public HttpResponseStreamWriter(Stream stream, Encoding encoding)
@@ -64,16 +66,16 @@ namespace Microsoft.AspNet.Mvc
             }
 
             _encoder = encoding.GetEncoder();
-            _byteBuffer = new ArraySegment<byte>(new byte[encoding.GetMaxByteCount(bufferSize)]);
+            _byteBuffer = new byte[encoding.GetMaxByteCount(bufferSize)];
-            _charBuffer = new ArraySegment<char>(new char[bufferSize]);
+            _charBuffer = new char[bufferSize];
         }
 
         public HttpResponseStreamWriter(
             Stream stream,
             Encoding encoding,
             int bufferSize,
-            LeasedArraySegment<byte> leasedByteBuffer,
+            ArrayPool<byte> bytePool,
-            LeasedArraySegment<char> leasedCharBuffer)
+            ArrayPool<char> charPool)
         {
             if (stream == null)
             {
@@ -90,59 +92,71 @@ namespace Microsoft.AspNet.Mvc
                 throw new ArgumentNullException(nameof(encoding));
             }
 
-            if (leasedByteBuffer == null)
+            if (bytePool == null)
             {
-                throw new ArgumentNullException(nameof(leasedByteBuffer));
+                throw new ArgumentNullException(nameof(bytePool));
             }
 
-            if (leasedCharBuffer == null)
+            if (charPool == null)
             {
-                throw new ArgumentNullException(nameof(leasedCharBuffer));
+                throw new ArgumentNullException(nameof(charPool));
-            }
-
-            if (bufferSize <= 0 || bufferSize > leasedCharBuffer.Data.Count)
-            {
-                throw new ArgumentOutOfRangeException(nameof(bufferSize));
-            }
-
-            var requiredLength = encoding.GetMaxByteCount(bufferSize);
-            if (requiredLength > leasedByteBuffer.Data.Count)
-            {
-                var message = Resources.FormatHttpResponseStreamWriter_InvalidBufferSize(
-                    requiredLength,
-                    bufferSize,
-                    encoding.EncodingName,
-                    typeof(Encoding).FullName,
-                    nameof(Encoding.GetMaxByteCount));
-                throw new ArgumentException(message, nameof(leasedByteBuffer));
             }
 
             _stream = stream;
             Encoding = encoding;
             _charBufferSize = bufferSize;
-            _leasedByteBuffer = leasedByteBuffer;
-            _leasedCharBuffer = leasedCharBuffer;
 
             _encoder = encoding.GetEncoder();
-            _byteBuffer = leasedByteBuffer.Data;
+            _bytePool = bytePool;
-            _charBuffer = leasedCharBuffer.Data;
+            _charPool = charPool;
+
+            _charBuffer = charPool.Rent(bufferSize);
+
+            try
+            {
+                var requiredLength = encoding.GetMaxByteCount(bufferSize);
+                _byteBuffer = bytePool.Rent(requiredLength);
+            }
+            catch
+            {
+                charPool.Return(_charBuffer);
+                _charBuffer = null;
+
+                if (_byteBuffer != null)
+                {
+                    bytePool.Return(_byteBuffer);
+                    _byteBuffer = null;
+                }
+
+                throw;
+            }
         }
 
         public override Encoding Encoding { get; }
 
         public override void Write(char value)
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             if (_charBufferCount == _charBufferSize)
             {
                 FlushInternal();
             }
 
-            _charBuffer.Array[_charBuffer.Offset + _charBufferCount] = value;
+            _charBuffer[_charBufferCount] = value;
             _charBufferCount++;
         }
 
         public override void Write(char[] values, int index, int count)
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             if (values == null)
             {
                 return;
@@ -161,6 +175,11 @@ namespace Microsoft.AspNet.Mvc
 
         public override void Write(string value)
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             if (value == null)
             {
                 return;
@@ -181,17 +200,27 @@ namespace Microsoft.AspNet.Mvc
 
         public override async Task WriteAsync(char value)
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             if (_charBufferCount == _charBufferSize)
             {
                 await FlushInternalAsync();
             }
 
-            _charBuffer.Array[_charBuffer.Offset + _charBufferCount] = value;
+            _charBuffer[_charBufferCount] = value;
             _charBufferCount++;
         }
 
         public override async Task WriteAsync(char[] values, int index, int count)
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             if (values == null)
             {
                 return;
@@ -210,6 +239,11 @@ namespace Microsoft.AspNet.Mvc
 
         public override async Task WriteAsync(string value)
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             if (value == null)
             {
                 return;
@@ -233,11 +267,21 @@ namespace Microsoft.AspNet.Mvc
 
         public override void Flush()
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             FlushInternal(true, true);
         }
 
         public override Task FlushAsync()
         {
+            if (_stream == null)
+            {
+                throw new ObjectDisposedException("stream");
+            }
+
             return FlushInternalAsync(flushStream: true, flushEncoder: true);
         }
 
@@ -245,7 +289,7 @@ namespace Microsoft.AspNet.Mvc
         // sent in chunked encoding in case of Helios.
         protected override void Dispose(bool disposing)
         {
-            if (disposing)
+            if (disposing && _stream != null)
             {
                 try
                 {
@@ -253,14 +297,18 @@ namespace Microsoft.AspNet.Mvc
                 }
                 finally
                 {
-                    if (_leasedByteBuffer != null)
+                    _stream = null;
+
+                    if (_bytePool != null)
                     {
-                        _leasedByteBuffer.Owner.Return(_leasedByteBuffer);
+                        _bytePool.Return(_byteBuffer);
+                        _byteBuffer = null;
                     }
 
-                    if (_leasedCharBuffer != null)
+                    if (_charPool != null)
                     {
-                        _leasedCharBuffer.Owner.Return(_leasedCharBuffer);
+                        _charPool.Return(_charBuffer);
+                        _charBuffer = null;
                     }
                 }
             }
@@ -274,16 +322,16 @@ namespace Microsoft.AspNet.Mvc
             }
 
             var count = _encoder.GetBytes(
-                _charBuffer.Array,
+                _charBuffer,
-                _charBuffer.Offset,
+                0,
                 _charBufferCount,
-                _byteBuffer.Array,
+                _byteBuffer,
-                _byteBuffer.Offset,
+                0,
                 flushEncoder);
 
             if (count > 0)
             {
-                _stream.Write(_byteBuffer.Array, _byteBuffer.Offset, count);
+                _stream.Write(_byteBuffer, 0, count);
             }
 
             _charBufferCount = 0;
@@ -302,16 +350,16 @@ namespace Microsoft.AspNet.Mvc
             }
 
             var count = _encoder.GetBytes(
-                _charBuffer.Array,
+                _charBuffer,
-                _charBuffer.Offset,
+                0,
                 _charBufferCount,
-                _byteBuffer.Array,
+                _byteBuffer,
-                _byteBuffer.Offset,
+                0,
                 flushEncoder);
 
             if (count > 0)
             {
-                await _stream.WriteAsync(_byteBuffer.Array, _byteBuffer.Offset, count);
+                await _stream.WriteAsync(_byteBuffer, 0, count);
             }
 
             _charBufferCount = 0;
@@ -328,8 +376,8 @@ namespace Microsoft.AspNet.Mvc
 
             value.CopyTo(
                 sourceIndex: index,
-                destination: _charBuffer.Array,
+                destination: _charBuffer,
-                destinationIndex: _charBuffer.Offset + _charBufferCount,
+                destinationIndex: _charBufferCount,
                 count: remaining);
 
             _charBufferCount += remaining;
@@ -344,8 +392,8 @@ namespace Microsoft.AspNet.Mvc
             Buffer.BlockCopy(
                 src: values,
                 srcOffset: index * sizeof(char),
-                dst: _charBuffer.Array,
+                dst: _charBuffer,
-                dstOffset: (_charBuffer.Offset + _charBufferCount) * sizeof(char),
+                dstOffset: _charBufferCount * sizeof(char),
                 count: remaining * sizeof(char));
 
             _charBufferCount += remaining;

src/Microsoft.AspNet.Mvc.Core/Infrastructure/HttpRequestStreamReader.cs

@@ -2,12 +2,12 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Buffers;
 using System.Diagnostics;
 using System.IO;
 using System.Text;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Mvc.Core;
-using Microsoft.Extensions.MemoryPool;
 
 namespace Microsoft.AspNet.Mvc.Infrastructure
 {
@@ -21,12 +21,12 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
         private readonly Encoding _encoding;
         private readonly Decoder _decoder;
 
-        private readonly LeasedArraySegment<byte> _leasedByteBuffer;
+        private readonly ArrayPool<byte> _bytePool;
-        private readonly LeasedArraySegment<char> _leasedCharBuffer;
+        private readonly ArrayPool<char> _charPool;
 
         private readonly int _byteBufferSize;
-        private readonly ArraySegment<byte> _byteBuffer;
+        private byte[] _byteBuffer;
-        private readonly ArraySegment<char> _charBuffer;
+        private char[] _charBuffer;
 
         private int _charBufferIndex;
         private int _charsRead;
@@ -66,17 +66,17 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
             }
 
             _byteBufferSize = bufferSize;
-            _byteBuffer = new ArraySegment<byte>(new byte[bufferSize]);
+            _byteBuffer = new byte[bufferSize];
             var maxCharsPerBuffer = encoding.GetMaxCharCount(bufferSize);
-            _charBuffer = new ArraySegment<char>(new char[maxCharsPerBuffer]);
+            _charBuffer = new char[maxCharsPerBuffer];
         }
 
         public HttpRequestStreamReader(
             Stream stream,
             Encoding encoding,
             int bufferSize,
-            LeasedArraySegment<byte> leasedByteBuffer,
+            ArrayPool<byte> bytePool,
-            LeasedArraySegment<char> leasedCharBuffer)
+            ArrayPool<char> charPool)
         {
             if (stream == null)
             {
@@ -93,42 +93,47 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 throw new ArgumentNullException(nameof(encoding));
             }
 
-            if (leasedByteBuffer == null)
+            if (bytePool == null)
             {
-                throw new ArgumentNullException(nameof(leasedByteBuffer));
+                throw new ArgumentNullException(nameof(bytePool));
             }
 
-            if (leasedCharBuffer == null)
+            if (charPool == null)
             {
-                throw new ArgumentNullException(nameof(leasedCharBuffer));
+                throw new ArgumentNullException(nameof(charPool));
             }
 
-            if (bufferSize <= 0 || bufferSize > leasedByteBuffer.Data.Count)
+            if (bufferSize <= 0)
             {
                 throw new ArgumentOutOfRangeException(nameof(bufferSize));
             }
 
-            var requiredLength = encoding.GetMaxCharCount(bufferSize);
-            if (requiredLength > leasedCharBuffer.Data.Count)
-            {
-                var message = Resources.FormatHttpRequestStreamReader_InvalidBufferSize(
-                    requiredLength,
-                    bufferSize,
-                    encoding.EncodingName,
-                    typeof(Encoding).FullName,
-                    nameof(Encoding.GetMaxCharCount));
-                throw new ArgumentException(message, nameof(leasedCharBuffer));
-            }
-
             _stream = stream;
             _encoding = encoding;
             _byteBufferSize = bufferSize;
-            _leasedByteBuffer = leasedByteBuffer;
+            _bytePool = bytePool;
-            _leasedCharBuffer = leasedCharBuffer;
+            _charPool = charPool;
 
             _decoder = encoding.GetDecoder();
-            _byteBuffer = _leasedByteBuffer.Data;
+
-            _charBuffer = _leasedCharBuffer.Data;
+            _byteBuffer = _bytePool.Rent(bufferSize);
+
+            try
+            {
+                var requiredLength = encoding.GetMaxCharCount(bufferSize);
+                _charBuffer = _charPool.Rent(requiredLength);
+            }
+            catch
+            {
+                _bytePool.Return(_byteBuffer);
+                _byteBuffer = null;
+
+                if (_charBuffer != null)
+                {
+                    _charPool.Return(_charBuffer);
+                    _charBuffer = null;
+                }
+            }
         }
 
 #if dnx451 
@@ -144,14 +149,16 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
             {
                 _stream = null;
 
-                if (_leasedByteBuffer != null)
+                if (_bytePool != null)
                 {
-                    _leasedByteBuffer.Owner.Return(_leasedByteBuffer);
+                    _bytePool.Return(_byteBuffer);
+                    _byteBuffer = null;
                 }
 
-                if (_leasedCharBuffer != null)
+                if (_charPool != null)
                 {
-                    _leasedCharBuffer.Owner.Return(_leasedCharBuffer);
+                    _charPool.Return(_charBuffer);
+                    _charBuffer = null;
                 }
             }
 
@@ -173,7 +180,7 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 }
             }
 
-            return _charBuffer.Array[_charBuffer.Offset + _charBufferIndex];
+            return _charBuffer[_charBufferIndex];
         }
 
         public override int Read()
@@ -191,7 +198,7 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 }
             }
 
-            return _charBuffer.Array[_charBuffer.Offset + _charBufferIndex++];
+            return _charBuffer[_charBufferIndex++];
         }
 
         public override int Read(char[] buffer, int index, int count)
@@ -236,8 +243,8 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 }
 
                 Buffer.BlockCopy(
-                    _charBuffer.Array,
+                    _charBuffer,
-                    (_charBuffer.Offset + _charBufferIndex) * 2,
+                    _charBufferIndex * 2,
                     buffer,
                     (index + charsRead) * 2,
                     charsRemaining * 2);
@@ -303,8 +310,8 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                     {
                         Debug.Assert(n == 0);
                         _bytesRead = await _stream.ReadAsync(
-                            _byteBuffer.Array,
+                            _byteBuffer,
-                            _byteBuffer.Offset,
+                            0,
                             _byteBufferSize);
                         if (_bytesRead == 0)  // EOF
                         {
@@ -319,12 +326,12 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
 
                         _charBufferIndex = 0;
                         n = _decoder.GetChars(
-                            _byteBuffer.Array,
+                            _byteBuffer,
-                            _byteBuffer.Offset,
+                            0,
                             _bytesRead,
-                            _charBuffer.Array,
+                            _charBuffer,
-                            _charBuffer.Offset);
+                            0);
-                        
+
                         Debug.Assert(n > 0);
 
                         _charsRead += n; // Number of chars in StreamReader's buffer.
@@ -344,8 +351,8 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 }
 
                 Buffer.BlockCopy(
-                    _charBuffer.Array,
+                    _charBuffer,
-                    (_charBuffer.Offset + _charBufferIndex) * 2,
+                    _charBufferIndex * 2,
                     buffer,
                     (index + charsRead) * 2,
                     n * 2);
@@ -375,7 +382,7 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
 
             do
             {
-                _bytesRead = _stream.Read(_byteBuffer.Array, _byteBuffer.Offset, _byteBufferSize);
+                _bytesRead = _stream.Read(_byteBuffer, 0, _byteBufferSize);
                 if (_bytesRead == 0)  // We're at EOF
                 {
                     return _charsRead;
@@ -383,11 +390,11 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
 
                 _isBlocked = (_bytesRead < _byteBufferSize);
                 _charsRead += _decoder.GetChars(
-                    _byteBuffer.Array,
+                    _byteBuffer,
-                    _byteBuffer.Offset,
+                    0,
                     _bytesRead,
-                    _charBuffer.Array,
+                    _charBuffer,
-                    _charBuffer.Offset + _charsRead);
+                    _charsRead);
             }
             while (_charsRead == 0);
 
@@ -404,8 +411,8 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
             {
 
                 _bytesRead = await _stream.ReadAsync(
-                    _byteBuffer.Array,
+                    _byteBuffer,
-                    _byteBuffer.Offset,
+                    0,
                     _byteBufferSize).ConfigureAwait(false);
                 if (_bytesRead == 0)
                 {
@@ -417,11 +424,11 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 _isBlocked = (_bytesRead < _byteBufferSize);
 
                 _charsRead += _decoder.GetChars(
-                    _byteBuffer.Array,
+                    _byteBuffer,
-                    _byteBuffer.Offset,
+                    0,
                     _bytesRead,
-                    _charBuffer.Array,
+                    _charBuffer,
-                    _charBuffer.Offset + _charsRead);
+                    _charsRead);
             }
             while (_charsRead == 0);
 

src/Microsoft.AspNet.Mvc.Core/Infrastructure/MemoryPoolHttpRequestStreamReaderFactory.cs

@@ -2,9 +2,9 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Buffers;
 using System.IO;
 using System.Text;
-using Microsoft.Extensions.MemoryPool;
 
 namespace Microsoft.AspNet.Mvc.Infrastructure
 {
@@ -18,21 +18,21 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
         /// </summary>
         public static readonly int DefaultBufferSize = 1024; // 1KB - results in a 4KB byte array for UTF8.
 
-        private readonly IArraySegmentPool<byte> _bytePool;
+        private readonly ArrayPool<byte> _bytePool;
-        private readonly IArraySegmentPool<char> _charPool;
+        private readonly ArrayPool<char> _charPool;
 
         /// <summary>
         /// Creates a new <see cref="MemoryPoolHttpRequestStreamReaderFactory"/>.
         /// </summary>
         /// <param name="bytePool">
-        /// The <see cref="IArraySegmentPool{byte}"/> for creating <see cref="byte"/> buffers.
+        /// The <see cref="ArrayPool{byte}"/> for creating <see cref="byte"/> buffers.
         /// </param>
         /// <param name="charPool">
-        /// The <see cref="IArraySegmentPool{char}"/> for creating <see cref="char"/> buffers.
+        /// The <see cref="ArrayPool{char}"/> for creating <see cref="char"/> buffers.
         /// </param>
         public MemoryPoolHttpRequestStreamReaderFactory(
-            IArraySegmentPool<byte> bytePool,
+            ArrayPool<byte> bytePool,
-            IArraySegmentPool<char> charPool)
+            ArrayPool<char> charPool)
         {
             if (bytePool == null)
             {
@@ -61,34 +61,7 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 throw new ArgumentNullException(nameof(encoding));
             }
 
-            LeasedArraySegment<byte> bytes = null;
+            return new HttpRequestStreamReader(stream, encoding, DefaultBufferSize, _bytePool, _charPool);
-            LeasedArraySegment<char> chars = null;
-
-            try
-            {
-                bytes = _bytePool.Lease(DefaultBufferSize);
-
-                // We need to compute the minimum size of the char buffer based on the size of the byte buffer,
-                // so that we have enough room to encode the buffer in one shot.
-                var minimumSize = encoding.GetMaxCharCount(DefaultBufferSize);
-                chars = _charPool.Lease(minimumSize);
-
-                return new HttpRequestStreamReader(stream, encoding, DefaultBufferSize, bytes, chars);
-            }
-            catch
-            {
-                if (bytes != null)
-                {
-                    bytes.Owner.Return(bytes);
-                }
-
-                if (chars != null)
-                {
-                    chars.Owner.Return(chars);
-                }
-
-                throw;
-            }
         }
     }
 }

src/Microsoft.AspNet.Mvc.Core/Infrastructure/MemoryPoolHttpResponseStreamWriterFactory.cs

@@ -2,9 +2,9 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Buffers;
 using System.IO;
 using System.Text;
-using Microsoft.Extensions.MemoryPool;
 
 namespace Microsoft.AspNet.Mvc.Infrastructure
 {
@@ -18,21 +18,21 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
         /// </summary>
         public static readonly int DefaultBufferSize = 1024; // 1KB - results in a 4KB byte array for UTF8.
 
-        private readonly IArraySegmentPool<byte> _bytePool;
+        private readonly ArrayPool<byte> _bytePool;
-        private readonly IArraySegmentPool<char> _charPool;
+        private readonly ArrayPool<char> _charPool;
 
         /// <summary>
         /// Creates a new <see cref="MemoryPoolHttpResponseStreamWriterFactory"/>.
         /// </summary>
         /// <param name="bytePool">
-        /// The <see cref="IArraySegmentPool{byte}"/> for creating <see cref="byte"/> buffers.
+        /// The <see cref="ArrayPool{byte}"/> for creating <see cref="byte"/> buffers.
         /// </param>
         /// <param name="charPool">
-        /// The <see cref="IArraySegmentPool{char}"/> for creating <see cref="char"/> buffers.
+        /// The <see cref="ArrayPool{char}"/> for creating <see cref="char"/> buffers.
         /// </param>
         public MemoryPoolHttpResponseStreamWriterFactory(
-            IArraySegmentPool<byte> bytePool,
+            ArrayPool<byte> bytePool,
-            IArraySegmentPool<char> charPool)
+            ArrayPool<char> charPool)
         {
             if (bytePool == null)
             {
@@ -61,34 +61,7 @@ namespace Microsoft.AspNet.Mvc.Infrastructure
                 throw new ArgumentNullException(nameof(encoding));
             }
 
-            LeasedArraySegment<byte> bytes = null;
+            return new HttpResponseStreamWriter(stream, encoding, DefaultBufferSize, _bytePool, _charPool);
-            LeasedArraySegment<char> chars = null;
-
-            try
-            {
-                chars = _charPool.Lease(DefaultBufferSize);
-
-                // We need to compute the minimum size of the byte buffer based on the size of the char buffer,
-                // so that we have enough room to encode the buffer in one shot.
-                var minimumSize = encoding.GetMaxByteCount(DefaultBufferSize);
-                bytes = _bytePool.Lease(minimumSize);
-
-                return new HttpResponseStreamWriter(stream, encoding, DefaultBufferSize, bytes, chars);
-            }
-            catch
-            {
-                if (bytes != null)
-                {
-                    bytes.Owner.Return(bytes);
-                }
-
-                if (chars != null)
-                {
-                    chars.Owner.Return(chars);
-                }
-
-                throw;
-            }
         }
     }
 }

src/Microsoft.AspNet.Mvc.Core/Properties/Resources.Designer.cs

@@ -970,22 +970,6 @@ namespace Microsoft.AspNet.Mvc.Core
             return string.Format(CultureInfo.CurrentCulture, GetString("ValueProviderResult_NoConverterExists"), p0, p1);
         }
 
-        /// <summary>
-        /// The byte buffer must have a length of at least '{0}' to be used with a char buffer of size '{1}' and encoding '{2}'. Use '{3}.{4}' to compute the correct size for the byte buffer.
-        /// </summary>
-        internal static string HttpResponseStreamWriter_InvalidBufferSize
-        {
-            get { return GetString("HttpResponseStreamWriter_InvalidBufferSize"); }
-        }
-
-        /// <summary>
-        /// The byte buffer must have a length of at least '{0}' to be used with a char buffer of size '{1}' and encoding '{2}'. Use '{3}.{4}' to compute the correct size for the byte buffer.
-        /// </summary>
-        internal static string FormatHttpResponseStreamWriter_InvalidBufferSize(object p0, object p1, object p2, object p3, object p4)
-        {
-            return string.Format(CultureInfo.CurrentCulture, GetString("HttpResponseStreamWriter_InvalidBufferSize"), p0, p1, p2, p3, p4);
-        }
-
         /// <summary>
         /// Path '{0}' was not rooted.
         /// </summary>
@@ -1018,22 +1002,6 @@ namespace Microsoft.AspNet.Mvc.Core
             return GetString("UrlNotLocal");
         }
 
-        /// <summary>
-        /// The char buffer must have a length of at least '{0}' to be used with a byte buffer of size '{1}' and encoding '{2}'. Use '{3}.{4}' to compute the correct size for the char buffer.
-        /// </summary>
-        internal static string HttpRequestStreamReader_InvalidBufferSize
-        {
-            get { return GetString("HttpRequestStreamReader_InvalidBufferSize"); }
-        }
-
-        /// <summary>
-        /// The char buffer must have a length of at least '{0}' to be used with a byte buffer of size '{1}' and encoding '{2}'. Use '{3}.{4}' to compute the correct size for the char buffer.
-        /// </summary>
-        internal static string FormatHttpRequestStreamReader_InvalidBufferSize(object p0, object p1, object p2, object p3, object p4)
-        {
-            return string.Format(CultureInfo.CurrentCulture, GetString("HttpRequestStreamReader_InvalidBufferSize"), p0, p1, p2, p3, p4);
-        }
-
         /// <summary>
         /// The stream must support reading.
         /// </summary>

src/Microsoft.AspNet.Mvc.Core/Resources.resx

@@ -306,9 +306,6 @@
   <data name="ValueProviderResult_NoConverterExists" xml:space="preserve">
     <value>The parameter conversion from type '{0}' to type '{1}' failed because no type converter can convert between these types.</value>
   </data>
-  <data name="HttpResponseStreamWriter_InvalidBufferSize" xml:space="preserve">
-    <value>The byte buffer must have a length of at least '{0}' to be used with a char buffer of size '{1}' and encoding '{2}'. Use '{3}.{4}' to compute the correct size for the byte buffer.</value>
-  </data>
   <data name="FileResult_PathNotRooted" xml:space="preserve">
     <value>Path '{0}' was not rooted.</value>
     <comment>{0} is the path which wasn't rooted</comment>
@@ -316,9 +313,6 @@
   <data name="UrlNotLocal" xml:space="preserve">
     <value>The supplied URL is not local. A URL with an absolute path is considered local if it does not have a host/authority part. URLs using virtual paths ('~/') are also local.</value>
   </data>
-  <data name="HttpRequestStreamReader_InvalidBufferSize" xml:space="preserve">
-    <value>The char buffer must have a length of at least '{0}' to be used with a byte buffer of size '{1}' and encoding '{2}'. Use '{3}.{4}' to compute the correct size for the char buffer.</value>
-  </data>
   <data name="HttpRequestStreamReader_StreamNotReadable" xml:space="preserve">
     <value>The stream must support reading.</value>
   </data>

src/Microsoft.AspNet.Mvc.Core/project.json

@@ -26,7 +26,6 @@
       "type": "build"
     },
     "Microsoft.Extensions.Logging.Abstractions": "1.0.0-*",
-    "Microsoft.Extensions.MemoryPool": "1.0.0-*",
     "Microsoft.Extensions.PropertyActivator.Sources": {
       "version": "1.0.0-*",
       "type": "build"
@@ -39,6 +38,7 @@
       "version": "1.0.0-*",
       "type": "build"
     },
+    "System.Buffers": "4.0.0-*",
     "System.Diagnostics.DiagnosticSource": "4.0.0-*"
   },
   "frameworks": {

src/Microsoft.AspNet.Mvc.Razor/project.json

@@ -26,7 +26,8 @@
       "type": "build"
     },
     "Microsoft.Dnx.Compilation.CSharp.Common": "1.0.0-*",
-    "Microsoft.Dnx.Compilation.CSharp.Abstractions": "1.0.0-*"
+    "Microsoft.Dnx.Compilation.CSharp.Abstractions": "1.0.0-*",
+    "Microsoft.Extensions.MemoryPool": "1.0.0-*"
   },
   "frameworks": {
     "net451": {

src/Microsoft.AspNet.Mvc.ViewFeatures/DependencyInjection/MvcViewFeaturesMvcCoreBuilderExtensions.cs

@@ -13,7 +13,6 @@ using Microsoft.AspNet.Mvc.ViewFeatures;
 using Microsoft.AspNet.Mvc.ViewFeatures.Buffer;
 using Microsoft.AspNet.Mvc.ViewFeatures.Internal;
 using Microsoft.Extensions.DependencyInjection.Extensions;
-using Microsoft.Extensions.MemoryPool;
 using Microsoft.Extensions.OptionsModel;
 
 namespace Microsoft.Extensions.DependencyInjection

test/Microsoft.AspNet.Mvc.Core.Test/HttpResponseStreamWriterTest.cs

@@ -1,12 +1,12 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System.Buffers;
 using System.IO;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Testing;
-using Microsoft.Extensions.MemoryPool;
 using Xunit;
 
 namespace Microsoft.AspNet.Mvc
@@ -384,98 +384,21 @@ namespace Microsoft.AspNet.Mvc
 
             var expectedBytes = encoding.GetBytes("Hello, World!");
 
-            using (var bytePool = new DefaultArraySegmentPool<byte>())
+            using (var writer = new HttpResponseStreamWriter(
+                stream,
+                encoding,
+                1024,
+                ArrayPool<byte>.Shared,
+                ArrayPool<char>.Shared))
             {
-                using (var charPool = new DefaultArraySegmentPool<char>())
+                // Act
-                {
+                writer.Write("Hello, World!");
-                    LeasedArraySegment<byte> bytes = null;
-                    LeasedArraySegment<char> chars = null;
-                    HttpResponseStreamWriter writer;
-
-                    try
-                    {
-                        bytes = bytePool.Lease(4096);
-                        chars = charPool.Lease(1024);
-
-                        writer = new HttpResponseStreamWriter(stream, encoding, 1024, bytes, chars);
-                    }
-                    catch
-                    {
-                        if (bytes != null)
-                        {
-                            bytes.Owner.Return(bytes);
-                        }
-
-                        if (chars != null)
-                        {
-                            chars.Owner.Return(chars);
-                        }
-
-                        throw;
-                    }
-
-                    // Act
-                    using (writer)
-                    {
-                        writer.Write("Hello, World!");
-                    }
-                }
             }
 
             // Assert
             Assert.Equal(expectedBytes, stream.ToArray());
         }
 
-        // This covers the error case where the byte buffer is too small. This is a safeguard, and shouldn't happen 
-        // if we're using the writer factory.
-        [Fact]
-        public void HttpResponseStreamWriter_UsingPooledBuffers_SmallByteBuffer()
-        {
-            // Arrange
-            var encoding = Encoding.UTF8;
-            var stream = new MemoryStream();
-
-            var message =
-                "The byte buffer must have a length of at least '12291' to be used with a char buffer of " +
-                "size '4096' and encoding 'Unicode (UTF-8)'. Use 'System.Text.Encoding.GetMaxByteCount' " +
-                "to compute the correct size for the byte buffer.";
-
-            using (var bytePool = new DefaultArraySegmentPool<byte>())
-            {
-                using (var charPool = new DefaultArraySegmentPool<char>())
-                {
-                    LeasedArraySegment<byte> bytes = null;
-                    LeasedArraySegment<char> chars = null;
-                    HttpResponseStreamWriter writer = null;
-
-                    try
-                    {
-                        bytes = bytePool.Lease(1024);
-                        chars = charPool.Lease(4096);
-
-                        // Act & Assert
-                        ExceptionAssert.ThrowsArgument(
-                            () => writer = new HttpResponseStreamWriter(stream, encoding, chars.Data.Count, bytes, chars),
-                            "byteBuffer",
-                            message);
-                        writer.Dispose();
-                    }
-                    catch
-                    {
-                        if (bytes != null)
-                        {
-                            bytes.Owner.Return(bytes);
-                        }
-
-                        if (chars != null)
-                        {
-                            chars.Owner.Return(chars);
-                        }
-                    }
-                }
-            }
-        }
-
         private class TestMemoryStream : MemoryStream
         {
             private int _flushCallCount;

test/Microsoft.AspNet.Mvc.Core.Test/Infrastructure/MemoryPoolHttpResponseStreamWriterFactoryTest.cs

@@ -1,50 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.IO;
-using System.Text;
-using Microsoft.Extensions.MemoryPool;
-using Moq;
-using Xunit;
-
-namespace Microsoft.AspNet.Mvc.Infrastructure
-{
-    public class MemoryPoolHttpResponseStreamWriterFactoryTest
-    {
-        [Fact]
-        public void CreateWriter_BuffersReturned_OnException()
-        {
-            // Arrange
-            var bytePool = new Mock<IArraySegmentPool<byte>>(MockBehavior.Strict);
-            bytePool
-                .Setup(p => p.Lease(It.IsAny<int>()))
-                .Returns(new LeasedArraySegment<byte>(new ArraySegment<byte>(new byte[4096]), bytePool.Object));
-            bytePool
-                .Setup(p => p.Return(It.IsAny<LeasedArraySegment<byte>>()))
-                .Verifiable();
-
-            var charPool = new Mock<IArraySegmentPool<char>>(MockBehavior.Strict);
-            charPool
-                .Setup(p => p.Lease(MemoryPoolHttpResponseStreamWriterFactory.DefaultBufferSize))
-                .Returns(new LeasedArraySegment<char>(new ArraySegment<char>(new char[4096]), charPool.Object));
-            charPool
-                .Setup(p => p.Return(It.IsAny<LeasedArraySegment<char>>()))
-                .Verifiable();
-
-            var encoding = new Mock<Encoding>();
-            encoding
-                .Setup(e => e.GetEncoder())
-                .Throws(new InvalidOperationException());
-
-            var factory = new MemoryPoolHttpResponseStreamWriterFactory(bytePool.Object, charPool.Object);
-
-            // Act
-            Assert.Throws<InvalidOperationException>(() => factory.CreateWriter(new MemoryStream(), encoding.Object));
-
-            // Assert
-            bytePool.Verify();
-            charPool.Verify();
-        }
-    }
-}