Allocate things per KestrelThread instead of per listener

- Moved things that have loop affinity to KestrelThread like
WriteReqPool, MemoryPool and the ConnectionManager
- Changed on the listeners to only kill the ListenSocket, not the
connections on dispose
- Moved connection disposal to KestrelThread.Stop
- Simplify the connection manager logic so it's possible to walk and
wait in a single call

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/Connection.cs

@@ -52,8 +52,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                 _bufferSizeControl = new BufferSizeControl(ServerOptions.MaxRequestBufferSize.Value, this, Thread);
             }
 
-            SocketInput = new SocketInput(Memory, ThreadPool, _bufferSizeControl);
+            SocketInput = new SocketInput(Thread.Memory, ThreadPool, _bufferSizeControl);
-            SocketOutput = new SocketOutput(Thread, _socket, Memory, this, ConnectionId, Log, ThreadPool, WriteReqPool);
+            SocketOutput = new SocketOutput(Thread, _socket, this, ConnectionId, Log, ThreadPool);
 
             var tcpHandle = _socket as UvTcpHandle;
             if (tcpHandle != null)
@@ -166,7 +166,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         {
             if (_filterContext.Connection != _libuvStream)
             {
-                _filteredStreamAdapter = new FilteredStreamAdapter(ConnectionId, _filterContext.Connection, Memory, Log, ThreadPool, _bufferSizeControl);
+                _filteredStreamAdapter = new FilteredStreamAdapter(ConnectionId, _filterContext.Connection, Thread.Memory, Log, ThreadPool, _bufferSizeControl);
 
                 _frame.SocketInput = _filteredStreamAdapter.SocketInput;
                 _frame.SocketOutput = _filteredStreamAdapter.SocketOutput;

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/ConnectionManager.cs

@@ -3,30 +3,36 @@
 
 using System;
 using System.Collections.Generic;
+using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Networking;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 {
     public class ConnectionManager
     {
-        private KestrelThread _thread;
+        private readonly KestrelThread _thread;
-        private List<Task> _connectionStopTasks;
+        private readonly IThreadPool _threadPool;
 
-        public ConnectionManager(KestrelThread thread)
+        public ConnectionManager(KestrelThread thread, IThreadPool threadPool)
         {
             _thread = thread;
+            _threadPool = threadPool;
         }
 
-        // This must be called on the libuv event loop
+        public bool WalkConnectionsAndClose(TimeSpan timeout)
-        public void WalkConnectionsAndClose()
         {
-            if (_connectionStopTasks != null)
+            var wh = new ManualResetEventSlim();
-            {
-                throw new InvalidOperationException($"{nameof(WalkConnectionsAndClose)} cannot be called twice.");
-            }
 
-            _connectionStopTasks = new List<Task>();
+            _thread.Post(state => ((ConnectionManager)state).WalkConnectionsAndCloseCore(wh), this);
+
+            return wh.Wait(timeout);
+        }
+
+        private void WalkConnectionsAndCloseCore(ManualResetEventSlim wh)
+        {
+            var connectionStopTasks = new List<Task>();
 
             _thread.Walk(ptr =>
             {
@@ -35,19 +41,15 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
                 if (connection != null)
                 {
-                    _connectionStopTasks.Add(connection.StopAsync());
+                    connectionStopTasks.Add(connection.StopAsync());
                 }
             });
-        }
 
-        public Task WaitForConnectionCloseAsync()
+            _threadPool.Run(() =>
-        {
-            if (_connectionStopTasks == null)
             {
-                throw new InvalidOperationException($"{nameof(WalkConnectionsAndClose)} must be called first.");
+                Task.WaitAll(connectionStopTasks.ToArray());
-            }
+                wh.Set();
-
+            });
-            return Task.WhenAll(_connectionStopTasks);
         }
     }
 }

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/Listener.cs

@@ -28,7 +28,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         {
             ServerAddress = address;
             Thread = thread;
-            ConnectionManager = new ConnectionManager(thread);
 
             var tcs = new TaskCompletionSource<int>(this);
 
@@ -57,7 +56,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
         protected static void ConnectionCallback(UvStreamHandle stream, int status, Exception error, object state)
         {
-            var listener = (Listener) state;
+            var listener = (Listener)state;
 
             if (error != null)
             {
@@ -97,22 +96,9 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
                     listener._closed = true;
 
-                    listener.ConnectionManager.WalkConnectionsAndClose();
-                }, this).ConfigureAwait(false);
-
-                await ConnectionManager.WaitForConnectionCloseAsync().ConfigureAwait(false);
-
-                await Thread.PostAsync(state =>
-                {
-                    var writeReqPool = ((Listener)state).WriteReqPool;
-                    while (writeReqPool.Count > 0)
-                    {
-                        writeReqPool.Dequeue().Dispose();
-                    }
                 }, this).ConfigureAwait(false);
             }
 
-            Memory.Dispose();
             ListenSocket = null;
         }
     }

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/ListenerContext.cs

@@ -16,8 +16,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         public ListenerContext(ServiceContext serviceContext) 
             : base(serviceContext)
         {
-            Memory = new MemoryPool();
-            WriteReqPool = new Queue<UvWriteReq>(SocketOutput.MaxPooledWriteReqs);
         }
 
         public ListenerContext(ListenerContext listenerContext)
@@ -25,20 +23,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         {
             ServerAddress = listenerContext.ServerAddress;
             Thread = listenerContext.Thread;
-            Memory = listenerContext.Memory;
-            ConnectionManager = listenerContext.ConnectionManager;
-            WriteReqPool = listenerContext.WriteReqPool;
-            Log = listenerContext.Log;
         }
 
         public ServerAddress ServerAddress { get; set; }
 
         public KestrelThread Thread { get; set; }
-
-        public MemoryPool Memory { get; set; }
-
-        public ConnectionManager ConnectionManager { get; set; }
-
-        public Queue<UvWriteReq> WriteReqPool { get; set; }
     }
 }

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/ListenerSecondary.cs

@@ -39,8 +39,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
             ServerAddress = address;
             Thread = thread;
-            ConnectionManager = new ConnectionManager(thread);
-
             DispatchPipe = new UvPipeHandle(Log);
 
             var tcs = new TaskCompletionSource<int>(this);
@@ -180,27 +178,12 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
                     listener._closed = true;
 
-                    listener.ConnectionManager.WalkConnectionsAndClose();
-                }, this).ConfigureAwait(false);
-
-                await ConnectionManager.WaitForConnectionCloseAsync().ConfigureAwait(false);
-
-                await Thread.PostAsync(state =>
-                {
-                    var listener = (ListenerSecondary)state;
-                    var writeReqPool = listener.WriteReqPool;
-                    while (writeReqPool.Count > 0)
-                    {
-                        writeReqPool.Dequeue().Dispose();
-                    }
                 }, this).ConfigureAwait(false);
             }
             else
             {
                 FreeBuffer();
             }
-
-            Memory.Dispose();
         }
     }
 }

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/SocketOutput.cs

@@ -14,8 +14,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 {
     public class SocketOutput : ISocketOutput
     {
-        public const int MaxPooledWriteReqs = 1024;
-
         private const int _maxPendingWrites = 3;
         private const int _maxBytesPreCompleted = 65536;
         // Well behaved WriteAsync users should await returned task, so there is no need to allocate more per connection by default
@@ -58,17 +56,15 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         private WriteContext _nextWriteContext;
         private readonly Queue<WaitingTask> _tasksPending;
         private readonly Queue<WriteContext> _writeContextPool;
-        private readonly Queue<UvWriteReq> _writeReqPool;
+        private readonly WriteReqPool _writeReqPool;
 
         public SocketOutput(
             KestrelThread thread,
             UvStreamHandle socket,
-            MemoryPool memory,
             Connection connection,
             string connectionId,
             IKestrelTrace log,
-            IThreadPool threadPool,
+            IThreadPool threadPool)
-            Queue<UvWriteReq> writeReqPool)
         {
             _thread = thread;
             _socket = socket;
@@ -78,9 +74,9 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             _threadPool = threadPool;
             _tasksPending = new Queue<WaitingTask>(_initialTaskQueues);
             _writeContextPool = new Queue<WriteContext>(_maxPooledWriteContexts);
-            _writeReqPool = writeReqPool;
+            _writeReqPool = thread.WriteReqPool;
 
-            _head = memory.Lease();
+            _head = thread.Memory.Lease();
             _tail = _head;
         }
 
@@ -585,15 +581,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                 var lockedEndBlock = _lockedEnd.Block;
                 var lockedEndIndex = _lockedEnd.Index;
 
-                if (Self._writeReqPool.Count > 0)
+                _writeReq = Self._writeReqPool.Allocate();
-                {
-                    _writeReq = Self._writeReqPool.Dequeue();
-                }
-                else
-                {
-                    _writeReq = new UvWriteReq(Self._log);
-                    _writeReq.Init(Self._thread.Loop);
-                }
 
                 _writeReq.Write(Self._socket, _lockedStart, _lockedEnd, _bufferCount, (_writeReq, status, error, state) =>
                 {
@@ -691,14 +679,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
             private void PoolWriteReq(UvWriteReq writeReq)
             {
-                if (Self._writeReqPool.Count < MaxPooledWriteReqs)
+                Self._writeReqPool.Return(writeReq);
-                {
-                    Self._writeReqPool.Enqueue(writeReq);
-                }
-                else
-                {
-                    writeReq.Dispose();
-                }
             }
 
             private void ScheduleReturnFullyWrittenBlocks()

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Infrastructure/KestrelThread.cs

@@ -7,6 +7,7 @@ using System.Runtime.ExceptionServices;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Http;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Networking;
 using Microsoft.Extensions.Logging;
@@ -42,6 +43,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal
         private ExceptionDispatchInfo _closeError;
         private readonly IKestrelTrace _log;
         private readonly IThreadPool _threadPool;
+        private readonly TimeSpan _shutdownTimeout;
 
         public KestrelThread(KestrelEngine engine)
         {
@@ -49,6 +51,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal
             _appLifetime = engine.AppLifetime;
             _log = engine.Log;
             _threadPool = engine.ThreadPool;
+            _shutdownTimeout = engine.ServerOptions.ShutdownTimeout;
             _loop = new UvLoopHandle(_log);
             _post = new UvAsyncHandle(_log);
             _thread = new Thread(ThreadStart);
@@ -60,10 +63,19 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal
 #endif
             QueueCloseHandle = PostCloseHandle;
             QueueCloseAsyncHandle = EnqueueCloseHandle;
+            Memory = new MemoryPool();
+            WriteReqPool = new WriteReqPool(this, _log);
+            ConnectionManager = new ConnectionManager(this, _threadPool);
         }
 
         public UvLoopHandle Loop { get { return _loop; } }
 
+        public MemoryPool Memory { get; }
+
+        public ConnectionManager ConnectionManager { get; }
+
+        public WriteReqPool WriteReqPool { get; }
+
         public ExceptionDispatchInfo FatalError { get { return _closeError; } }
 
         public Action<Action<IntPtr>, IntPtr> QueueCloseHandle { get; }
@@ -95,6 +107,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal
 
             if (_thread.IsAlive)
             {
+                // These operations need to run on the libuv thread so it only makes
+                // sense to attempt execution if it's still running
+                DisposeConnections();
+
                 var stepTimeout = (int)(timeout.TotalMilliseconds / 2);
                 try
                 {
@@ -125,6 +141,34 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal
             }
         }
 
+        private void DisposeConnections()
+        {
+            try
+            {
+                // Close and wait for all connections
+                if (!ConnectionManager.WalkConnectionsAndClose(_shutdownTimeout))
+                {
+                    _log.LogError(0, null, "Waiting for connections timed out");
+                }
+
+                var result = PostAsync(state =>
+                {
+                    var listener = (KestrelThread)state;
+                    listener.WriteReqPool.Dispose();
+                },
+                this).Wait(_shutdownTimeout);
+
+                if (!result)
+                {
+                    _log.LogError(0, null, "Disposing write requests failed");
+                }
+            }
+            finally
+            {
+                Memory.Dispose();
+            }
+        }
+
         private void OnStopRude()
         {
             Walk(ptr =>

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Infrastructure/WriteReqPool.cs

@@ -0,0 +1,73 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Networking;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
+{
+    public class WriteReqPool
+    {
+        private const int _maxPooledWriteReqs = 1024;
+
+        private readonly KestrelThread _thread;
+        private readonly Queue<UvWriteReq> _pool = new Queue<UvWriteReq>(_maxPooledWriteReqs);
+        private readonly IKestrelTrace _log;
+        private bool _disposed;
+
+        public WriteReqPool(KestrelThread thread, IKestrelTrace log)
+        {
+            _thread = thread;
+            _log = log;
+        }
+
+        public UvWriteReq Allocate()
+        {
+            if (_disposed)
+            {
+                throw new ObjectDisposedException(GetType().Name);
+            }
+
+            UvWriteReq req;
+            if (_pool.Count > 0)
+            {
+                req = _pool.Dequeue();
+            }
+            else
+            {
+                req = new UvWriteReq(_log);
+                req.Init(_thread.Loop);
+            }
+
+            return req;
+        }
+
+        public void Return(UvWriteReq req)
+        {
+            if (_disposed)
+            {
+                throw new ObjectDisposedException(GetType().Name);
+            }
+
+            if (_pool.Count < _maxPooledWriteReqs)
+            {
+                _pool.Enqueue(req);
+            }
+            else
+            {
+                req.Dispose();
+            }
+        }
+
+        public void Dispose()
+        {
+            if (!_disposed)
+            {
+                _disposed = true;
+
+                while (_pool.Count > 0)
+                {
+                    _pool.Dequeue().Dispose();
+                }
+            }
+        }
+    }
+}

test/Microsoft.AspNetCore.Server.KestrelTests/ConnectionTests.cs

@@ -17,7 +17,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         {
             var mockLibuv = new MockLibuv();
 
-            using (var memory = new MemoryPool())
             using (var engine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 engine.Start(count: 1);
@@ -27,7 +26,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 {
                     FrameFactory = connectionContext => new Frame<HttpContext>(
                         new DummyApplication(httpContext => TaskUtilities.CompletedTask), connectionContext),
-                    Memory = memory,
                     ServerAddress = ServerAddress.FromUrl("http://127.0.0.1:0"),
                     Thread = engine.Threads[0]
                 };

test/Microsoft.AspNetCore.Server.KestrelTests/SocketOutputTests.cs

@@ -26,8 +26,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 
             // Arrange
             var mockLibuv = new MockLibuv();
-
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -36,7 +34,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var socket = new MockSocket(mockLibuv, kestrelThread.Loop.ThreadId, new TestKestrelTrace());
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, new MockConnection(), "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, new MockConnection(), "0", trace, ltp);
 
                 // I doubt _maxBytesPreCompleted will ever be over a MB. If it is, we should change this test.
                 var bufferSize = 1048576;
@@ -78,7 +76,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -88,7 +85,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
                 var mockConnection = new MockConnection();
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, mockConnection, "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, mockConnection, "0", trace, ltp);
 
                 var bufferSize = maxBytesPreCompleted;
                 var buffer = new ArraySegment<byte>(new byte[bufferSize], 0, bufferSize);
@@ -152,7 +149,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -162,7 +158,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
                 var mockConnection = new MockConnection();
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, mockConnection, "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, mockConnection, "0", trace, ltp);
 
                 var bufferSize = maxBytesPreCompleted / 2;
                 var data = new byte[bufferSize];
@@ -231,7 +227,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -243,7 +238,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 
                 using (var mockConnection = new MockConnection())
                 {
-                    ISocketOutput socketOutput = new SocketOutput(kestrelThread, socket, memory, mockConnection, "0", trace, ltp, new Queue<UvWriteReq>());
+                    ISocketOutput socketOutput = new SocketOutput(kestrelThread, socket, mockConnection, "0", trace, ltp);
 
                     var bufferSize = maxBytesPreCompleted;
 
@@ -348,7 +343,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -361,7 +355,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 using (var mockConnection = new MockConnection())
                 {
                     var abortedSource = mockConnection.RequestAbortedSource;
-                    ISocketOutput socketOutput = new SocketOutput(kestrelThread, socket, memory, mockConnection, "0", trace, ltp, new Queue<UvWriteReq>());
+                    ISocketOutput socketOutput = new SocketOutput(kestrelThread, socket, mockConnection, "0", trace, ltp);
 
                     var bufferSize = maxBytesPreCompleted;
 
@@ -441,7 +435,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -451,7 +444,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
                 var mockConnection = new MockConnection();
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, mockConnection, "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, mockConnection, "0", trace, ltp);
 
                 var bufferSize = maxBytesPreCompleted;
                 var buffer = new ArraySegment<byte>(new byte[bufferSize], 0, bufferSize);
@@ -534,7 +527,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -543,14 +535,14 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var socket = new MockSocket(mockLibuv, kestrelThread.Loop.ThreadId, new TestKestrelTrace());
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, new MockConnection(), "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, new MockConnection(), "0", trace, ltp);
 
                 // block 1
                 var start = socketOutput.ProducingStart();
                 start.Block.End = start.Block.Data.Offset + start.Block.Data.Count;
 
                 // block 2
-                var block2 = memory.Lease();
+                var block2 = kestrelThread.Memory.Lease();
                 block2.End = block2.Data.Offset + block2.Data.Count;
                 start.Block.Next = block2;
 
@@ -586,7 +578,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -596,7 +587,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
                 var mockConnection = new MockConnection();
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, mockConnection, "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, mockConnection, "0", trace, ltp);
 
                 var buffer = new ArraySegment<byte>(new byte[1]);
 
@@ -656,7 +647,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             };
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -665,7 +655,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var socket = new MockSocket(mockLibuv, kestrelThread.Loop.ThreadId, new TestKestrelTrace());
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, new MockConnection(), "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, new MockConnection(), "0", trace, ltp);
 
                 var blockThreadWh = new ManualResetEventSlim();
                 kestrelThread.Post(_ =>
@@ -702,7 +692,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         {
             var mockLibuv = new MockLibuv();
 
-            using (var memory = new MemoryPool())
             using (var kestrelEngine = new KestrelEngine(mockLibuv, new TestServiceContext()))
             {
                 kestrelEngine.Start(count: 1);
@@ -712,7 +701,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 var trace = new KestrelTrace(new TestKestrelTrace());
                 var ltp = new LoggingThreadPool(trace);
                 var connection = new MockConnection();
-                var socketOutput = new SocketOutput(kestrelThread, socket, memory, connection, "0", trace, ltp, new Queue<UvWriteReq>());
+                var socketOutput = new SocketOutput(kestrelThread, socket, connection, "0", trace, ltp);
 
                 // Close SocketOutput
                 var cleanupTask = socketOutput.WriteAsync(