Adding example of what http context pooling might look like

samples/SampleApp/PooledHttpContext.cs

@@ -0,0 +1,54 @@
+// 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 Microsoft.AspNet.Http;
+using Microsoft.AspNet.Http.Features;
+using Microsoft.AspNet.Http.Internal;
+
+namespace SampleApp
+{
+    public class PooledHttpContext : DefaultHttpContext
+    {
+        DefaultHttpRequest _pooledHttpRequest;
+        DefaultHttpResponse _pooledHttpResponse;
+
+        public PooledHttpContext(IFeatureCollection featureCollection) : 
+            base(featureCollection)
+        {
+        }
+
+        protected override HttpRequest InitializeHttpRequest()
+        {
+            if (_pooledHttpRequest != null)
+            {
+                _pooledHttpRequest.Initialize(this, Features);
+                return _pooledHttpRequest;
+            }
+
+            return new DefaultHttpRequest(this, Features);
+        }
+
+        protected override void UninitializeHttpRequest(HttpRequest instance)
+        {
+            _pooledHttpRequest = instance as DefaultHttpRequest;
+            _pooledHttpRequest?.Uninitialize();
+        }
+
+        protected override HttpResponse InitializeHttpResponse()
+        {
+            if (_pooledHttpResponse != null)
+            {
+                _pooledHttpResponse.Initialize(this, Features);
+                return _pooledHttpResponse;
+            }
+
+            return new DefaultHttpResponse(this, Features);
+        }
+
+        protected override void UninitializeHttpResponse(HttpResponse instance)
+        {
+            _pooledHttpResponse = instance as DefaultHttpResponse;
+            _pooledHttpResponse?.Uninitialize();
+        }
+    }
+}

samples/SampleApp/PooledHttpContextFactory.cs

@@ -0,0 +1,65 @@
+// 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.Collections.Generic;
+using Microsoft.AspNet.Http;
+using Microsoft.AspNet.Http.Features;
+
+namespace SampleApp
+{
+    public class PooledHttpContextFactory : IHttpContextFactory
+    {
+        private readonly IHttpContextAccessor _httpContextAccessor;
+        private readonly Stack<PooledHttpContext> _pool = new Stack<PooledHttpContext>();
+
+        public PooledHttpContextFactory(IHttpContextAccessor httpContextAccessor)
+        {
+            _httpContextAccessor = httpContextAccessor;
+        }
+
+        public HttpContext Create(IFeatureCollection featureCollection)
+        {
+            PooledHttpContext httpContext = null;
+            lock (_pool)
+            {
+                if (_pool.Count != 0)
+                {
+                    httpContext = _pool.Pop();
+                }
+            }
+
+            if (httpContext == null)
+            {
+                httpContext = new PooledHttpContext(featureCollection);
+            }
+            else
+            {
+                httpContext.Initialize(featureCollection);
+            }
+
+            if (_httpContextAccessor != null)
+            {
+                _httpContextAccessor.HttpContext = httpContext;
+            }
+            return httpContext;
+        }
+
+        public void Dispose(HttpContext httpContext)
+        {
+            if (_httpContextAccessor != null)
+            {
+                _httpContextAccessor.HttpContext = null;
+            }
+
+            var pooled = httpContext as PooledHttpContext;
+            if (pooled != null)
+            {
+                pooled.Uninitialize();
+                lock (_pool)
+                {
+                    _pool.Push(pooled);
+                }
+            }
+        }
+    }
+}

src/Microsoft.AspNet.Http/DefaultHttpRequest.cs

@@ -16,7 +16,7 @@ namespace Microsoft.AspNet.Http.Internal
         private HttpContext _context;
         private FeatureReferences<FeatureInterfaces> _features;
 
-        public DefaultHttpRequest(DefaultHttpContext context, IFeatureCollection features)
+        public DefaultHttpRequest(HttpContext context, IFeatureCollection features)
         {
             Initialize(context, features);
         }

src/Microsoft.AspNet.Http/DefaultHttpResponse.cs

@@ -15,7 +15,7 @@ namespace Microsoft.AspNet.Http.Internal
         private HttpContext _context;
         private FeatureReferences<FeatureInterfaces> _features;
 
-        public DefaultHttpResponse(DefaultHttpContext context, IFeatureCollection features)
+        public DefaultHttpResponse(HttpContext context, IFeatureCollection features)
         {
             Initialize(context, features);
         }