React to pipeline changes (#2234)

React to pipeline changes

benchmarks/Kestrel.Performance/Http1ConnectionParsingOverheadBenchmark.cs

@@ -16,7 +16,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
     {
         private const int InnerLoopCount = 512;
 
-        public ReadableBuffer _buffer;
+        public ReadOnlyBuffer _buffer;
         public Http1Connection _http1Connection;
 
         [IterationSetup]

benchmarks/Kestrel.Performance/HttpParserBenchmark.cs

@@ -2,6 +2,7 @@
 // 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.Pipelines;
 using BenchmarkDotNet.Attributes;
 using Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http;
@@ -12,7 +13,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
     {
         private readonly HttpParser<Adapter> _parser = new HttpParser<Adapter>();
 
-        private ReadableBuffer _buffer;
+        private ReadOnlyBuffer _buffer;
 
         [Benchmark(Baseline = true, OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
         public void PlaintextTechEmpower()
@@ -46,7 +47,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
 
         private void InsertData(byte[] data)
         {
-            _buffer = ReadableBuffer.Create(data);
+            _buffer = new ReadOnlyBuffer(data);
         }
 
         private void ParseData()

benchmarks/Kestrel.Performance/Mocks/NullParser.cs

@@ -2,6 +2,8 @@
 // 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.Collections.Sequences;
 using System.IO.Pipelines;
 using System.Text;
 using Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http;
@@ -21,7 +23,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
 
         public static readonly NullParser<Http1ParsingHandler> Instance = new NullParser<Http1ParsingHandler>();
 
-        public bool ParseHeaders(TRequestHandler handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined, out int consumedBytes)
+        public bool ParseHeaders(TRequestHandler handler, ReadOnlyBuffer buffer, out Position consumed, out Position examined, out int consumedBytes)
         {
             handler.OnHeader(new Span<byte>(_hostHeaderName), new Span<byte>(_hostHeaderValue));
             handler.OnHeader(new Span<byte>(_acceptHeaderName), new Span<byte>(_acceptHeaderValue));
@@ -34,7 +36,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
             return true;
         }
 
-        public bool ParseRequestLine(TRequestHandler handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+        public bool ParseRequestLine(TRequestHandler handler, ReadOnlyBuffer buffer, out Position consumed, out Position examined)
         {
             handler.OnStartLine(HttpMethod.Get,
                 HttpVersion.Http11,

build/dependencies.props

@@ -25,20 +25,21 @@
     <MicrosoftExtensionsLoggingTestingPackageVersion>2.1.0-preview1-27965</MicrosoftExtensionsLoggingTestingPackageVersion>
     <MicrosoftExtensionsOptionsPackageVersion>2.1.0-preview1-27965</MicrosoftExtensionsOptionsPackageVersion>
     <MicrosoftNETCoreApp20PackageVersion>2.0.0</MicrosoftNETCoreApp20PackageVersion>
-    <MicrosoftNETCoreApp21PackageVersion>2.1.0-preview1-26016-05</MicrosoftNETCoreApp21PackageVersion>
+    <MicrosoftNETCoreApp21PackageVersion>2.1.0-preview1-26102-01</MicrosoftNETCoreApp21PackageVersion>
     <MicrosoftNetHttpHeadersPackageVersion>2.1.0-preview1-27965</MicrosoftNetHttpHeadersPackageVersion>
     <MicrosoftNETTestSdkPackageVersion>15.3.0</MicrosoftNETTestSdkPackageVersion>
     <MoqPackageVersion>4.7.49</MoqPackageVersion>
     <NewtonsoftJsonPackageVersion>10.0.1</NewtonsoftJsonPackageVersion>
-    <SystemBuffersPackageVersion>4.5.0-preview1-26016-05</SystemBuffersPackageVersion>
+    <SystemBuffersPackageVersion>4.5.0-preview1-26102-01</SystemBuffersPackageVersion>
-    <SystemIOPipelinesPackageVersion>0.1.0-e171215-1</SystemIOPipelinesPackageVersion>
+    <SystemBuffersPrimitivesPackageVersion>0.1.0-e180104-2</SystemBuffersPrimitivesPackageVersion>
-    <SystemIOPipelinesTestingPackageVersion>0.1.0-e171215-1</SystemIOPipelinesTestingPackageVersion>
+    <SystemIOPipelinesPackageVersion>0.1.0-e180104-2</SystemIOPipelinesPackageVersion>
-    <SystemMemoryPackageVersion>4.5.0-preview1-26016-05</SystemMemoryPackageVersion>
+    <SystemIOPipelinesTestingPackageVersion>0.1.0-e180104-2</SystemIOPipelinesTestingPackageVersion>
-    <SystemNumericsVectorsPackageVersion>4.5.0-preview1-26016-05</SystemNumericsVectorsPackageVersion>
+    <SystemMemoryPackageVersion>4.5.0-preview1-26102-01</SystemMemoryPackageVersion>
-    <SystemRuntimeCompilerServicesUnsafePackageVersion>4.5.0-preview1-26016-05</SystemRuntimeCompilerServicesUnsafePackageVersion>
+    <SystemNumericsVectorsPackageVersion>4.5.0-preview1-26102-01</SystemNumericsVectorsPackageVersion>
-    <SystemSecurityCryptographyCngPackageVersion>4.5.0-preview1-26016-05</SystemSecurityCryptographyCngPackageVersion>
+    <SystemRuntimeCompilerServicesUnsafePackageVersion>4.5.0-preview1-26102-01</SystemRuntimeCompilerServicesUnsafePackageVersion>
-    <SystemTextEncodingsWebUtf8PackageVersion>0.1.0-e171215-1</SystemTextEncodingsWebUtf8PackageVersion>
+    <SystemSecurityCryptographyCngPackageVersion>4.5.0-preview1-26102-01</SystemSecurityCryptographyCngPackageVersion>
-    <SystemThreadingTasksExtensionsPackageVersion>4.5.0-preview2-25707-02</SystemThreadingTasksExtensionsPackageVersion>
+    <SystemTextEncodingsWebUtf8PackageVersion>0.1.0-e180104-2</SystemTextEncodingsWebUtf8PackageVersion>
+    <SystemThreadingTasksExtensionsPackageVersion>4.5.0-preview1-26102-01</SystemThreadingTasksExtensionsPackageVersion>
     <XunitAnalyzersPackageVersion>0.8.0</XunitAnalyzersPackageVersion>
     <XunitPackageVersion>2.3.1</XunitPackageVersion>
     <XunitRunnerVisualStudioPackageVersion>2.3.1</XunitRunnerVisualStudioPackageVersion>

src/Kestrel.Core/Adapter/Internal/AdaptedPipeline.cs

@@ -6,6 +6,7 @@ using System.IO;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http;
 using System.IO.Pipelines;
+using System.Runtime.InteropServices;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Adapter.Internal
 {

src/Kestrel.Core/Internal/ConnectionHandler.cs

@@ -83,7 +83,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
         }
 
         // Internal for testing
-        internal static PipeOptions GetInputPipeOptions(ServiceContext serviceContext, MemoryPool memoryPool, IScheduler writerScheduler) => new PipeOptions
+        internal static PipeOptions GetInputPipeOptions(ServiceContext serviceContext, MemoryPool memoryPool, Scheduler writerScheduler) => new PipeOptions
         (
             pool: memoryPool,
             readerScheduler: serviceContext.ThreadPool,
@@ -92,7 +92,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             maximumSizeLow: serviceContext.ServerOptions.Limits.MaxRequestBufferSize ?? 0
         );
 
-        internal static PipeOptions GetOutputPipeOptions(ServiceContext serviceContext, MemoryPool memoryPool, IScheduler readerScheduler) => new PipeOptions
+        internal static PipeOptions GetOutputPipeOptions(ServiceContext serviceContext, MemoryPool memoryPool, Scheduler readerScheduler) => new PipeOptions
         (
             pool: memoryPool,
             readerScheduler: readerScheduler,

src/Kestrel.Core/Internal/Http/Http1Connection.cs

@@ -2,11 +2,14 @@
 // 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.Collections.Sequences;
 using System.Diagnostics;
 using System.IO.Pipelines;
 using System.Runtime.InteropServices;
 using System.Text;
 using System.Text.Encodings.Web.Utf8;
+using System.Threading;
 using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure;
 
@@ -66,7 +69,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             Input.CancelPendingRead();
         }
 
-        public void ParseRequest(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+        public void ParseRequest(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
         {
             consumed = buffer.Start;
             examined = buffer.End;
@@ -104,7 +107,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             }
         }
 
-        public bool TakeStartLine(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+        public bool TakeStartLine(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
         {
             var overLength = false;
             if (buffer.Length >= ServerOptions.Limits.MaxRequestLineSize)
@@ -122,7 +125,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             return result;
         }
 
-        public bool TakeMessageHeaders(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+        public bool TakeMessageHeaders(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
         {
             // Make sure the buffer is limited
             bool overLength = false;
@@ -424,7 +427,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             TimeoutControl.SetTimeout(_keepAliveTicks, TimeoutAction.StopProcessingNextRequest);
         }
 
-        protected override bool BeginRead(out ReadableBufferAwaitable awaitable)
+        protected override bool BeginRead(out ValueAwaiter<ReadResult> awaitable)
         {
             awaitable = Input.ReadAsync();
             return true;

src/Kestrel.Core/Internal/Http/Http1MessageBody.cs

@@ -2,6 +2,8 @@
 // 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.Collections.Sequences;
 using System.IO;
 using System.IO.Pipelines;
 using System.Threading.Tasks;
@@ -149,7 +151,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             }
         }
 
-        protected void Copy(ReadableBuffer readableBuffer, WritableBuffer writableBuffer)
+        protected void Copy(ReadOnlyBuffer readableBuffer, WritableBuffer writableBuffer)
         {
             _context.TimeoutControl.BytesRead(readableBuffer.Length);
 
@@ -171,7 +173,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             _pumpTask = PumpAsync();
         }
 
-        protected virtual bool Read(ReadableBuffer readableBuffer, WritableBuffer writableBuffer, out ReadCursor consumed, out ReadCursor examined)
+        protected virtual bool Read(ReadOnlyBuffer readableBuffer, WritableBuffer writableBuffer, out Position consumed, out Position examined)
         {
             throw new NotImplementedException();
         }
@@ -296,7 +298,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 RequestUpgrade = true;
             }
 
-            protected override bool Read(ReadableBuffer readableBuffer, WritableBuffer writableBuffer, out ReadCursor consumed, out ReadCursor examined)
+            protected override bool Read(ReadOnlyBuffer readableBuffer, WritableBuffer writableBuffer, out Position consumed, out Position examined)
             {
                 Copy(readableBuffer, writableBuffer);
                 consumed = readableBuffer.End;
@@ -318,7 +320,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 _inputLength = _contentLength;
             }
 
-            protected override bool Read(ReadableBuffer readableBuffer, WritableBuffer writableBuffer, out ReadCursor consumed, out ReadCursor examined)
+            protected override bool Read(ReadOnlyBuffer readableBuffer, WritableBuffer writableBuffer, out Position consumed, out Position examined)
             {
                 if (_inputLength == 0)
                 {
@@ -366,10 +368,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 RequestKeepAlive = keepAlive;
             }
 
-            protected override bool Read(ReadableBuffer readableBuffer, WritableBuffer writableBuffer, out ReadCursor consumed, out ReadCursor examined)
+            protected override bool Read(ReadOnlyBuffer readableBuffer, WritableBuffer writableBuffer, out Position consumed, out Position examined)
             {
-                consumed = default(ReadCursor);
+                consumed = default(Position);
-                examined = default(ReadCursor);
+                examined = default(Position);
 
                 while (_mode < Mode.Trailer)
                 {
@@ -457,17 +459,17 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 }
             }
 
-            private void ParseChunkedPrefix(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+            private void ParseChunkedPrefix(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
             {
                 consumed = buffer.Start;
                 examined = buffer.Start;
-                var reader = new ReadableBufferReader(buffer);
+                var reader = BufferReader.Create(buffer);
                 var ch1 = reader.Take();
                 var ch2 = reader.Take();
 
                 if (ch1 == -1 || ch2 == -1)
                 {
-                    examined = reader.Cursor;
+                    examined = reader.Position;
                     return;
                 }
 
@@ -478,8 +480,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 {
                     if (ch1 == ';')
                     {
-                        consumed = reader.Cursor;
+                        consumed = reader.Position;
-                        examined = reader.Cursor;
+                        examined = reader.Position;
 
                         AddAndCheckConsumedBytes(reader.ConsumedBytes);
                         _inputLength = chunkSize;
@@ -490,14 +492,14 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                     ch2 = reader.Take();
                     if (ch2 == -1)
                     {
-                        examined = reader.Cursor;
+                        examined = reader.Position;
                         return;
                     }
 
                     if (ch1 == '\r' && ch2 == '\n')
                     {
-                        consumed = reader.Cursor;
+                        consumed = reader.Position;
-                        examined = reader.Cursor;
+                        examined = reader.Position;
 
                         AddAndCheckConsumedBytes(reader.ConsumedBytes);
                         _inputLength = chunkSize;
@@ -513,7 +515,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 _context.ThrowRequestRejected(RequestRejectionReason.BadChunkSizeData);
             }
 
-            private void ParseExtension(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+            private void ParseExtension(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
             {
                 // Chunk-extensions not currently parsed
                 // Just drain the data
@@ -522,8 +524,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
 
                 do
                 {
-                    ReadCursor extensionCursor;
+                    Position extensionCursor;
-                    if (ReadCursorOperations.Seek(buffer.Start, buffer.End, out extensionCursor, ByteCR) == -1)
+                    if (ReadOnlyBuffer.Seek(buffer.Start, buffer.End, out extensionCursor, ByteCR) == -1)
                     {
                         // End marker not found yet
                         consumed = buffer.End;
@@ -565,7 +567,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 } while (_mode == Mode.Extension);
             }
 
-            private void ReadChunkedData(ReadableBuffer buffer, WritableBuffer writableBuffer, out ReadCursor consumed, out ReadCursor examined)
+            private void ReadChunkedData(ReadOnlyBuffer buffer, WritableBuffer writableBuffer, out Position consumed, out Position examined)
             {
                 var actual = Math.Min(buffer.Length, _inputLength);
                 consumed = buffer.Move(buffer.Start, actual);
@@ -582,7 +584,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 }
             }
 
-            private void ParseChunkedSuffix(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+            private void ParseChunkedSuffix(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
             {
                 consumed = buffer.Start;
                 examined = buffer.Start;
@@ -608,7 +610,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                 }
             }
 
-            private void ParseChunkedTrailer(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+            private void ParseChunkedTrailer(ReadOnlyBuffer buffer, out Position consumed, out Position examined)
             {
                 consumed = buffer.Start;
                 examined = buffer.Start;

src/Kestrel.Core/Internal/Http/Http1OutputProducer.cs

@@ -203,7 +203,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             return FlushAsyncAwaited(awaitable, bytesWritten, cancellationToken);
         }
 
-        private async Task FlushAsyncAwaited(WritableBufferAwaitable awaitable, long count, CancellationToken cancellationToken)
+        private async Task FlushAsyncAwaited(ValueAwaiter<FlushResult> awaitable, long count, CancellationToken cancellationToken)
         {
             // https://github.com/dotnet/corefxlab/issues/1334
             // Since the flush awaitable doesn't currently support multiple awaiters

src/Kestrel.Core/Internal/Http/HttpParser.cs

@@ -2,6 +2,8 @@
 // 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.Collections.Sequences;
 using System.IO.Pipelines;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
@@ -31,7 +33,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
         private const byte ByteQuestionMark = (byte)'?';
         private const byte BytePercentage = (byte)'%';
 
-        public unsafe bool ParseRequestLine(TRequestHandler handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+        public unsafe bool ParseRequestLine(TRequestHandler handler, ReadOnlyBuffer buffer, out Position consumed, out Position examined)
         {
             consumed = buffer.Start;
             examined = buffer.End;
@@ -186,7 +188,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             handler.OnStartLine(method, httpVersion, targetBuffer, pathBuffer, query, customMethod, pathEncoded);
         }
 
-        public unsafe bool ParseHeaders(TRequestHandler handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined, out int consumedBytes)
+        public unsafe bool ParseHeaders(TRequestHandler handler, ReadOnlyBuffer buffer, out Position consumed, out Position examined, out int consumedBytes)
         {
             consumed = buffer.Start;
             examined = buffer.End;
@@ -194,8 +196,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
 
             var bufferEnd = buffer.End;
 
-            var reader = new ReadableBufferReader(buffer);
+            var reader = BufferReader.Create(buffer);
-            var start = default(ReadableBufferReader);
+            var start = default(BufferReader<ReadOnlyBuffer>);
             var done = false;
 
             try
@@ -276,10 +278,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
                             }
                             else
                             {
-                                var current = reader.Cursor;
+                                var current = reader.Position;
 
                                 // Split buffers
-                                if (ReadCursorOperations.Seek(current, bufferEnd, out var lineEnd, ByteLF) == -1)
+                                if (ReadOnlyBuffer.Seek(current, bufferEnd, out var lineEnd, ByteLF) == -1)
                                 {
                                     // Not there
                                     return false;
@@ -312,7 +314,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             }
             finally
             {
-                consumed = reader.Cursor;
+                consumed = reader.Position;
                 consumedBytes = reader.ConsumedBytes;
 
                 if (done)
@@ -412,10 +414,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
         }
 
         [MethodImpl(MethodImplOptions.NoInlining)]
-        private static bool TryGetNewLine(ref ReadableBuffer buffer, out ReadCursor found)
+        private static bool TryGetNewLine(ref ReadOnlyBuffer buffer, out Position found)
         {
             var start = buffer.Start;
-            if (ReadCursorOperations.Seek(start, buffer.End, out found, ByteLF) != -1)
+            if (ReadOnlyBuffer.Seek(start, buffer.End, out found, ByteLF) != -1)
             {
                 // Move 1 byte past the \n
                 found = buffer.Move(found, 1);

src/Kestrel.Core/Internal/Http/HttpProtocol.cs

@@ -380,7 +380,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
         {
         }
 
-        protected virtual bool BeginRead(out ReadableBufferAwaitable awaitable)
+        protected virtual bool BeginRead(out ValueAwaiter<ReadResult> awaitable)
         {
             awaitable = default;
             return false;
@@ -1302,7 +1302,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             (
                 pool: _context.MemoryPool,
                 readerScheduler: ServiceContext.ThreadPool,
-                writerScheduler: InlineScheduler.Default,
+                writerScheduler: Scheduler.Inline,
                 maximumSizeHigh: 1,
                 maximumSizeLow: 1
             ));

src/Kestrel.Core/Internal/Http/IHttpParser.cs

@@ -1,14 +1,16 @@
 // 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.Collections.Sequences;
 using System.IO.Pipelines;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
 {
     public interface IHttpParser<TRequestHandler> where TRequestHandler : IHttpHeadersHandler, IHttpRequestLineHandler
     {
-        bool ParseRequestLine(TRequestHandler handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined);
+        bool ParseRequestLine(TRequestHandler handler, ReadOnlyBuffer buffer, out Position consumed, out Position examined);
 
-        bool ParseHeaders(TRequestHandler handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined, out int consumedBytes);
+        bool ParseHeaders(TRequestHandler handler, ReadOnlyBuffer buffer, out Position consumed, out Position examined, out int consumedBytes);
     }
-}
+}

src/Kestrel.Core/Internal/Http/PipelineExtensions.cs

@@ -2,6 +2,7 @@
 // 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.Pipelines;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
@@ -16,7 +17,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
         private static byte[] _numericBytesScratch;
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static Span<byte> ToSpan(this ReadableBuffer buffer)
+        public static ReadOnlySpan<byte> ToSpan(this ReadOnlyBuffer buffer)
         {
             if (buffer.IsSingleSpan)
             {
@@ -35,6 +36,15 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
             return result;
         }
 
+        public static ArraySegment<byte> GetArray(this ReadOnlyMemory<byte> memory)
+        {
+            if (!MemoryMarshal.TryGetArray(memory, out var result))
+            {
+                throw new InvalidOperationException("Buffer backed by array was expected");
+            }
+            return result;
+        }
+
         public unsafe static void WriteAsciiNoValidation(ref this WritableBufferWriter buffer, string data)
         {
             if (string.IsNullOrEmpty(data))

src/Kestrel.Core/Internal/Http2/Http2Connection.cs

@@ -2,6 +2,8 @@
 // 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.Collections.Sequences;
 using System.Collections.Concurrent;
 using System.IO.Pipelines;
 using System.Text;
@@ -214,7 +216,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2
             }
         }
 
-        private bool ParsePreface(ReadableBuffer readableBuffer, out ReadCursor consumed, out ReadCursor examined)
+        private bool ParsePreface(ReadOnlyBuffer readableBuffer, out Position consumed, out Position examined)
         {
             consumed = readableBuffer.Start;
             examined = readableBuffer.End;

src/Kestrel.Core/Internal/Http2/Http2FrameReader.cs

@@ -1,13 +1,15 @@
 // 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.Collections.Sequences;
 using System.IO.Pipelines;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2
 {
     public static class Http2FrameReader
     {
-        public static bool ReadFrame(ReadableBuffer readableBuffer, Http2Frame frame, out ReadCursor consumed, out ReadCursor examined)
+        public static bool ReadFrame(ReadOnlyBuffer readableBuffer, Http2Frame frame, out Position consumed, out Position examined)
         {
             consumed = readableBuffer.Start;
             examined = readableBuffer.End;

src/Kestrel.Core/Internal/HttpConnection.cs

@@ -73,7 +73,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
         (
             pool: MemoryPool,
             readerScheduler: _context.ServiceContext.ThreadPool,
-            writerScheduler: InlineScheduler.Default,
+            writerScheduler: Scheduler.Inline,
             maximumSizeHigh: _context.ServiceContext.ServerOptions.Limits.MaxRequestBufferSize ?? 0,
             maximumSizeLow: _context.ServiceContext.ServerOptions.Limits.MaxRequestBufferSize ?? 0
         );
@@ -81,8 +81,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
         internal PipeOptions AdaptedOutputPipeOptions => new PipeOptions
         (
             pool: MemoryPool,
-            readerScheduler: InlineScheduler.Default,
+            readerScheduler: Scheduler.Inline,
-            writerScheduler: InlineScheduler.Default,
+            writerScheduler: Scheduler.Inline,
             maximumSizeHigh: _context.ServiceContext.ServerOptions.Limits.MaxResponseBufferSize ?? 0,
             maximumSizeLow: _context.ServiceContext.ServerOptions.Limits.MaxResponseBufferSize ?? 0
         );

src/Kestrel.Core/Internal/Infrastructure/InlineLoggingThreadPool.cs

@@ -7,7 +7,7 @@ using Microsoft.Extensions.Logging;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
 {
-    public class InlineLoggingThreadPool : IThreadPool
+    public class InlineLoggingThreadPool : KestrelThreadPool
     {
         private readonly IKestrelTrace _log;
 
@@ -16,7 +16,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             _log = log;
         }
 
-        public void Run(Action action)
+        public override void Run(Action action)
         {
             try
             {
@@ -28,12 +28,17 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             }
         }
 
-        public void UnsafeRun(WaitCallback action, object state)
+        public override void UnsafeRun(WaitCallback action, object state)
         {
             action(state);
         }
 
-        public void Schedule(Action<object> action, object state)
+        public override void Schedule(Action action)
+        {
+            Run(action);
+        }
+
+        public override void Schedule(Action<object> action, object state)
         {
             try
             {

src/Kestrel.Core/Internal/Infrastructure/KestrelThreadPool.cs

@@ -7,9 +7,9 @@ using System.Threading;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
 {
-    public interface IThreadPool : IScheduler
+    public abstract class KestrelThreadPool: Scheduler
     {
-        void Run(Action action);
+        public abstract void Run(Action action);
-        void UnsafeRun(WaitCallback action, object state);
+        public abstract void UnsafeRun(WaitCallback action, object state);
     }
 }

src/Kestrel.Core/Internal/Infrastructure/LoggingThreadPool.cs

@@ -7,7 +7,7 @@ using Microsoft.Extensions.Logging;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
 {
-    public class LoggingThreadPool : IThreadPool
+    public class LoggingThreadPool : KestrelThreadPool
     {
         private readonly IKestrelTrace _log;
 
@@ -40,17 +40,22 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             };
         }
 
-        public void Run(Action action)
+        public override void Run(Action action)
         {
             ThreadPool.QueueUserWorkItem(_runAction, action);
         }
 
-        public void UnsafeRun(WaitCallback action, object state)
+        public override void UnsafeRun(WaitCallback action, object state)
         {
             ThreadPool.QueueUserWorkItem(action, state);
         }
 
-        public void Schedule(Action<object> action, object state)
+        public override void Schedule(Action action)
+        {
+            Run(action);
+        }
+
+        public override void Schedule(Action<object> action, object state)
         {
             Run(() => action(state));
         }

src/Kestrel.Core/Internal/ServiceContext.cs

@@ -11,7 +11,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
     {
         public IKestrelTrace Log { get; set; }
 
-        public IThreadPool ThreadPool { get; set; }
+        public KestrelThreadPool ThreadPool { get; set; }
 
         public IHttpParser<Http1ParsingHandler> HttpParser { get; set; }
 

src/Kestrel.Core/KestrelServer.cs

@@ -77,7 +77,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core
 
             // TODO: This logic will eventually move into the IConnectionHandler<T> and off
             // the service context once we get to https://github.com/aspnet/KestrelHttpServer/issues/1662
-            IThreadPool threadPool = null;
+            KestrelThreadPool threadPool = null;
             switch (serverOptions.ApplicationSchedulingMode)
             {
                 case SchedulingMode.Default:

src/Kestrel.Transport.Abstractions/Internal/TransportConnection.cs

@@ -23,8 +23,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Abstractions.Internal
         public string ConnectionId { get; set; }
 
         public virtual MemoryPool MemoryPool { get; }
-        public virtual IScheduler InputWriterScheduler { get; }
+        public virtual Scheduler InputWriterScheduler { get; }
-        public virtual IScheduler OutputReaderScheduler { get; }
+        public virtual Scheduler OutputReaderScheduler { get; }
 
         public IPipeConnection Transport { get; set; }
         public IPipeConnection Application { get; set; }

src/Kestrel.Transport.Libuv/Internal/LibuvConnection.cs

@@ -6,6 +6,7 @@ using System.Buffers;
 using System.Diagnostics;
 using System.IO;
 using System.IO.Pipelines;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Protocols;
 using Microsoft.AspNetCore.Server.Kestrel.Transport.Abstractions.Internal;
@@ -183,7 +184,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Internal
             _bufferHandle.Dispose();
         }
 
-        private async Task ApplyBackpressureAsync(WritableBufferAwaitable flushTask)
+        private async Task ApplyBackpressureAsync(ValueAwaiter<FlushResult> flushTask)
         {
             Log.ConnectionPause(ConnectionId);
             _socket.ReadStop();

src/Kestrel.Transport.Libuv/Internal/LibuvConnectionContext.cs

@@ -19,7 +19,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Internal
         public ListenerContext ListenerContext { get; set; }
 
         public override MemoryPool MemoryPool => ListenerContext.Thread.MemoryPool;
-        public override IScheduler InputWriterScheduler => ListenerContext.Thread;
+        public override Scheduler InputWriterScheduler => ListenerContext.Thread;
-        public override IScheduler OutputReaderScheduler => ListenerContext.Thread;
+        public override Scheduler OutputReaderScheduler => ListenerContext.Thread;
     }
 }

src/Kestrel.Transport.Libuv/Internal/LibuvThread.cs

@@ -15,7 +15,7 @@ using Microsoft.Extensions.Logging;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Internal
 {
-    public class LibuvThread : IScheduler
+    public class LibuvThread : Scheduler
     {
         // maximum times the work queues swapped and are processed in a single pass
         // as completing a task may immediately have write data to put on the network
@@ -390,7 +390,12 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Internal
             return await Task.WhenAny(task, Task.Delay(timeout)).ConfigureAwait(false) == task;
         }
 
-        public void Schedule(Action<object> action, object state)
+        public override void Schedule(Action action)
+        {
+            Post(state => state(), action);
+        }
+
+        public override void Schedule(Action<object> action, object state)
         {
             Post(action, state);
         }

src/Kestrel.Transport.Libuv/Internal/Networking/UvWriteReq.cs

@@ -49,7 +49,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Internal.Networkin
             _bufs = handle + requestSize;
         }
 
-        public LibuvAwaitable<UvWriteReq> WriteAsync(UvStreamHandle handle, ReadableBuffer buffer)
+        public LibuvAwaitable<UvWriteReq> WriteAsync(UvStreamHandle handle, ReadOnlyBuffer buffer)
         {
             Write(handle, buffer, LibuvAwaitable<UvWriteReq>.Callback, _awaitable);
             return _awaitable;
@@ -63,7 +63,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Internal.Networkin
 
         private unsafe void Write(
             UvStreamHandle handle,
-            ReadableBuffer buffer,
+            ReadOnlyBuffer buffer,
             Action<UvWriteReq, int, UvException, object> callback,
             object state)
         {

src/Kestrel.Transport.Sockets/Internal/BufferExtensions.cs

@@ -2,15 +2,24 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Runtime.InteropServices;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
 {
     public static class BufferExtensions
     {
-        public static ArraySegment<byte> GetArray(this Memory<byte> buffer)
+        public static ArraySegment<byte> GetArray(this Memory<byte> memory)
         {
-            ArraySegment<byte> result;
+            if (!memory.TryGetArray(out var result))
-            if (!buffer.TryGetArray(out result))
+            {
+                throw new InvalidOperationException("Buffer backed by array was expected");
+            }
+            return result;
+        }
+
+        public static ArraySegment<byte> GetArray(this ReadOnlyMemory<byte> memory)
+        {
+            if (!MemoryMarshal.TryGetArray(memory, out var result))
             {
                 throw new InvalidOperationException("Buffer backed by array was expected");
             }

src/Kestrel.Transport.Sockets/Internal/SocketConnection.cs

@@ -52,8 +52,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
         }
 
         public override MemoryPool MemoryPool { get; }
-        public override IScheduler InputWriterScheduler => InlineScheduler.Default;
+        public override Scheduler InputWriterScheduler => Scheduler.Inline;
-        public override IScheduler OutputReaderScheduler => TaskRunScheduler.Default;
+        public override Scheduler OutputReaderScheduler => Scheduler.TaskRun;
 
         public async Task StartAsync(IConnectionHandler connectionHandler)
         {

src/Kestrel.Transport.Sockets/Internal/SocketSender.cs

@@ -2,10 +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.Collections.Generic;
 using System.Diagnostics;
 using System.IO.Pipelines;
 using System.Net.Sockets;
+using System.Runtime.InteropServices;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
 {
@@ -24,7 +26,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
             _eventArgs.Completed += (_, e) => ((SocketAwaitable)e.UserToken).Complete(e.BytesTransferred, e.SocketError);
         }
 
-        public SocketAwaitable SendAsync(ReadableBuffer buffers)
+        public SocketAwaitable SendAsync(ReadOnlyBuffer buffers)
         {
             if (buffers.IsSingleSpan)
             {
@@ -50,7 +52,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
             return _awaitable;
         }
 
-        private SocketAwaitable SendAsync(Memory<byte> buffer)
+        private SocketAwaitable SendAsync(ReadOnlyMemory<byte> memory)
         {
             // The BufferList getter is much less expensive then the setter.
             if (_eventArgs.BufferList != null)
@@ -59,9 +61,9 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
             }
 
 #if NETCOREAPP2_1
-            _eventArgs.SetBuffer(buffer);
+            _eventArgs.SetBuffer(MemoryMarshal.AsMemory(memory));
 #else
-            var segment = buffer.GetArray();
+            var segment = memory.GetArray();
 
             _eventArgs.SetBuffer(segment.Array, segment.Offset, segment.Count);
 #endif
@@ -73,7 +75,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.Internal
             return _awaitable;
         }
 
-        private List<ArraySegment<byte>> GetBufferList(ReadableBuffer buffer)
+        private List<ArraySegment<byte>> GetBufferList(ReadOnlyBuffer buffer)
         {
             Debug.Assert(!buffer.IsEmpty);
             Debug.Assert(!buffer.IsSingleSpan);

src/Protocols.Abstractions/Features/IConnectionTransportFeature.cs

@@ -12,8 +12,8 @@ namespace Microsoft.AspNetCore.Protocols.Features
 
         IPipeConnection Application { get; set; }
 
-        IScheduler InputWriterScheduler { get; }
+        Scheduler InputWriterScheduler { get; }
 
-        IScheduler OutputReaderScheduler { get; }
+        Scheduler OutputReaderScheduler { get; }
     }
 }

test/Kestrel.Core.Tests/ConnectionHandlerTests.cs

@@ -58,9 +58,9 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             public IPipeConnection Transport { get; set; }
             public IPipeConnection Application { get; set; }
 
-            public IScheduler InputWriterScheduler => TaskRunScheduler.Default;
+            public Scheduler InputWriterScheduler => Scheduler.TaskRun;
 
-            public IScheduler OutputReaderScheduler => TaskRunScheduler.Default;
+            public Scheduler OutputReaderScheduler => Scheduler.TaskRun;
 
             public string ConnectionId { get; set; }
         }

test/Kestrel.Core.Tests/Http1ConnectionTests.cs

@@ -5,6 +5,7 @@ using System;
 using System.Buffers;
 using System.Collections;
 using System.Collections.Generic;
+using System.Collections.Sequences;
 using System.IO;
 using System.IO.Pipelines;
 using System.Linq;
@@ -33,8 +34,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
         private readonly ServiceContext _serviceContext;
         private readonly Http1ConnectionContext _http1ConnectionContext;
         private readonly MemoryPool _pipelineFactory;
-        private ReadCursor _consumed;
+        private Position _consumed;
-        private ReadCursor _examined;
+        private Position _examined;
         private Mock<ITimeoutControl> _timeoutControl;
 
         public Http1ConnectionTests()

test/Kestrel.Core.Tests/HttpParserTests.cs

@@ -2,8 +2,8 @@
 // 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.Pipelines;
-using System.IO.Pipelines.Testing;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
@@ -35,7 +35,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             string expectedVersion)
         {
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(requestLine));
             var requestHandler = new RequestHandler();
 
             Assert.True(parser.ParseRequestLine(requestHandler, buffer, out var consumed, out var examined));
@@ -54,7 +54,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
         public void ParseRequestLineReturnsFalseWhenGivenIncompleteRequestLines(string requestLine)
         {
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(requestLine));
             var requestHandler = new RequestHandler();
 
             Assert.False(parser.ParseRequestLine(requestHandler, buffer, out var consumed, out var examined));
@@ -65,7 +65,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
         public void ParseRequestLineDoesNotConsumeIncompleteRequestLine(string requestLine)
         {
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(requestLine));
             var requestHandler = new RequestHandler();
 
             Assert.False(parser.ParseRequestLine(requestHandler, buffer, out var consumed, out var examined));
@@ -84,7 +84,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
                 .Returns(true);
 
             var parser = CreateParser(mockTrace.Object);
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(requestLine));
             var requestHandler = new RequestHandler();
 
             var exception = Assert.Throws<BadHttpRequestException>(() =>
@@ -106,7 +106,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
                 .Returns(true);
 
             var parser = CreateParser(mockTrace.Object);
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(requestLine));
             var requestHandler = new RequestHandler();
 
             var exception = Assert.Throws<BadHttpRequestException>(() =>
@@ -128,7 +128,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
                 .Returns(true);
 
             var parser = CreateParser(mockTrace.Object);
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(requestLine));
             var requestHandler = new RequestHandler();
 
             var exception = Assert.Throws<BadHttpRequestException>(() =>
@@ -179,7 +179,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
         {
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
 
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(rawHeaders));
             var requestHandler = new RequestHandler();
             Assert.False(parser.ParseHeaders(requestHandler, buffer, out var consumed, out var examined, out var consumedBytes));
         }
@@ -204,7 +204,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
         {
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
 
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(rawHeaders));
             var requestHandler = new RequestHandler();
             parser.ParseHeaders(requestHandler, buffer, out var consumed, out var examined, out var consumedBytes);
 
@@ -294,7 +294,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
 
             const string headerLine = "Header: value\r\n\r";
-            var buffer1 = ReadableBuffer.Create(Encoding.ASCII.GetBytes(headerLine));
+            var buffer1 = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(headerLine));
             var requestHandler = new RequestHandler();
             Assert.False(parser.ParseHeaders(requestHandler, buffer1, out var consumed, out var examined, out var consumedBytes));
 
@@ -302,7 +302,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             Assert.Equal(buffer1.End, examined);
             Assert.Equal(headerLine.Length - 1, consumedBytes);
 
-            var buffer2 = ReadableBuffer.Create(Encoding.ASCII.GetBytes("\r\n"));
+            var buffer2 = new ReadOnlyBuffer(Encoding.ASCII.GetBytes("\r\n"));
             Assert.True(parser.ParseHeaders(requestHandler, buffer2, out consumed, out examined, out consumedBytes));
 
             Assert.Equal(buffer2.End, consumed);
@@ -320,7 +320,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
                 .Returns(true);
 
             var parser = CreateParser(mockTrace.Object);
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(rawHeaders));
             var requestHandler = new RequestHandler();
 
             var exception = Assert.Throws<BadHttpRequestException>(() =>
@@ -341,7 +341,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             var parser = CreateParser(mockTrace.Object);
 
             // Invalid request line
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes("GET % HTTP/1.1\r\n"));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes("GET % HTTP/1.1\r\n"));
             var requestHandler = new RequestHandler();
 
             var exception = Assert.Throws<BadHttpRequestException>(() =>
@@ -351,7 +351,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             Assert.Equal(StatusCodes.Status400BadRequest, (exception as BadHttpRequestException).StatusCode);
 
             // Unrecognized HTTP version
-            buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes("GET / HTTP/1.2\r\n"));
+            buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes("GET / HTTP/1.2\r\n"));
 
             exception = Assert.Throws<BadHttpRequestException>(() =>
                 parser.ParseRequestLine(requestHandler, buffer, out var consumed, out var examined));
@@ -360,7 +360,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             Assert.Equal(StatusCodes.Status505HttpVersionNotsupported, (exception as BadHttpRequestException).StatusCode);
 
             // Invalid request header
-            buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes("Header: value\n\r\n"));
+            buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes("Header: value\n\r\n"));
 
             exception = Assert.Throws<BadHttpRequestException>(() =>
                 parser.ParseHeaders(requestHandler, buffer, out var consumed, out var examined, out var consumedBytes));
@@ -369,27 +369,13 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             Assert.Equal(StatusCodes.Status400BadRequest, exception.StatusCode);
         }
 
-        [Fact]
-        public void ParseRequestLineSplitBufferWithoutNewLineDoesNotUpdateConsumed()
-        {
-            var parser = CreateParser(Mock.Of<IKestrelTrace>());
-            var buffer = BufferUtilities.CreateBuffer("GET ", "/");
-
-            var requestHandler = new RequestHandler();
-            var result = parser.ParseRequestLine(requestHandler, buffer, out var consumed, out var examined);
-
-            Assert.False(result);
-            Assert.Equal(buffer.Start, consumed);
-            Assert.Equal(buffer.End, examined);
-        }
-
         private void VerifyHeader(
             string headerName,
             string rawHeaderValue,
             string expectedHeaderValue)
         {
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes($"{headerName}:{rawHeaderValue}\r\n"));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes($"{headerName}:{rawHeaderValue}\r\n"));
 
             var requestHandler = new RequestHandler();
             parser.ParseHeaders(requestHandler, buffer, out var consumed, out var examined, out var consumedBytes);
@@ -407,7 +393,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             Assert.True(expectedHeaderNames.Count() == expectedHeaderValues.Count(), $"{nameof(expectedHeaderNames)} and {nameof(expectedHeaderValues)} sizes must match");
 
             var parser = CreateParser(Mock.Of<IKestrelTrace>());
-            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+            var buffer = new ReadOnlyBuffer(Encoding.ASCII.GetBytes(rawHeaders));
 
             var requestHandler = new RequestHandler();
             parser.ParseHeaders(requestHandler, buffer, out var consumed, out var examined, out var consumedBytes);

test/Kestrel.Core.Tests/OutputProducerTests.cs

@@ -33,7 +33,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             var pipeOptions = new PipeOptions
             (
                 pool: _memoryPool,
-                readerScheduler: Mock.Of<IScheduler>()
+                readerScheduler: Mock.Of<Scheduler>()
             );
 
             using (var socketOutput = CreateOutputProducer(pipeOptions))

test/Kestrel.Core.Tests/PipeOptionsTests.cs

@@ -26,7 +26,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             serviceContext.ServerOptions.Limits.MaxResponseBufferSize = maxResponseBufferSize;
             serviceContext.ThreadPool = new LoggingThreadPool(null);
 
-            var mockScheduler = Mock.Of<IScheduler>();
+            var mockScheduler = Mock.Of<Scheduler>();
             var outputPipeOptions = ConnectionHandler.GetOutputPipeOptions(serviceContext, new MemoryPool(), readerScheduler: mockScheduler);
 
             Assert.Equal(expectedMaximumSizeLow, outputPipeOptions.MaximumSizeLow);
@@ -44,7 +44,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             serviceContext.ServerOptions.Limits.MaxRequestBufferSize = maxRequestBufferSize;
             serviceContext.ThreadPool = new LoggingThreadPool(null);
 
-            var mockScheduler = Mock.Of<IScheduler>();
+            var mockScheduler = Mock.Of<Scheduler>();
             var inputPipeOptions = ConnectionHandler.GetInputPipeOptions(serviceContext, new MemoryPool(), writerScheduler: mockScheduler);
 
             Assert.Equal(expectedMaximumSizeLow, inputPipeOptions.MaximumSizeLow);
@@ -69,7 +69,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             Assert.Equal(expectedMaximumSizeLow, connectionLifetime.AdaptedInputPipeOptions.MaximumSizeLow);
             Assert.Equal(expectedMaximumSizeHigh, connectionLifetime.AdaptedInputPipeOptions.MaximumSizeHigh);
             Assert.Same(serviceContext.ThreadPool, connectionLifetime.AdaptedInputPipeOptions.ReaderScheduler);
-            Assert.Same(InlineScheduler.Default, connectionLifetime.AdaptedInputPipeOptions.WriterScheduler);
+            Assert.Same(Scheduler.Inline, connectionLifetime.AdaptedInputPipeOptions.WriterScheduler);
         }
 
         [Theory]
@@ -87,8 +87,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
 
             Assert.Equal(expectedMaximumSizeLow, connectionLifetime.AdaptedOutputPipeOptions.MaximumSizeLow);
             Assert.Equal(expectedMaximumSizeHigh, connectionLifetime.AdaptedOutputPipeOptions.MaximumSizeHigh);
-            Assert.Same(InlineScheduler.Default, connectionLifetime.AdaptedOutputPipeOptions.ReaderScheduler);
+            Assert.Same(Scheduler.Inline, connectionLifetime.AdaptedOutputPipeOptions.ReaderScheduler);
-            Assert.Same(InlineScheduler.Default, connectionLifetime.AdaptedOutputPipeOptions.WriterScheduler);
+            Assert.Same(Scheduler.Inline, connectionLifetime.AdaptedOutputPipeOptions.WriterScheduler);
         }
     }
 }

test/Kestrel.Transport.Libuv.Tests/LibuvConnectionTests.cs

@@ -117,11 +117,11 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Tests
             var transportContext = new TestLibuvTransportContext() { ConnectionHandler = mockConnectionHandler };
             var transport = new LibuvTransport(mockLibuv, transportContext, null);
             var thread = new LibuvThread(transport);
-            var mockScheduler = new Mock<IScheduler>();
+            var mockScheduler = new Mock<Scheduler>();
             Action backPressure = null;
-            mockScheduler.Setup(m => m.Schedule(It.IsAny<Action<object>>(), It.IsAny<object>())).Callback<Action<object>, object>((a, o) =>
+            mockScheduler.Setup(m => m.Schedule(It.IsAny<Action>())).Callback<Action>(a =>
             {
-                backPressure = () => a(o);
+                backPressure = a;
             });
             mockConnectionHandler.InputOptions = pool =>
                 new PipeOptions(

test/Kestrel.Transport.Libuv.Tests/MultipleLoopTests.cs

@@ -2,6 +2,7 @@
 // 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.Pipelines;
 using System.Net;
 using System.Net.Sockets;
@@ -68,7 +69,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Tests
 
                 await writeRequest.WriteAsync(
                     serverConnectionPipe,
-                    ReadableBuffer.Create(new byte[] { 1, 2, 3, 4 }));
+                    new ReadOnlyBuffer(new byte[] { 1, 2, 3, 4 }));
 
                 writeRequest.Dispose();
                 serverConnectionPipe.Dispose();

test/Kestrel.Transport.Libuv.Tests/NetworkingTests.cs

@@ -2,6 +2,7 @@
 // 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.Net;
 using System.Net.Sockets;
 using System.Runtime.InteropServices;
@@ -161,7 +162,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Tests
                             {
                                 var req = new UvWriteReq(_logger);
                                 req.DangerousInit(loop);
-                                var block = ReadableBuffer.Create(new byte[] { 65, 66, 67, 68, 69 });
+                                var block = new ReadOnlyBuffer(new byte[] { 65, 66, 67, 68, 69 });
 
                                 await req.WriteAsync(
                                     tcp2,