Merge branch 'khellang/configurable-thread-count' into dev

Author: halter73

src/Microsoft.AspNet.Server.Kestrel/KestrelServerInformation.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using Microsoft.AspNet.Server.Features;
 using Microsoft.AspNet.Server.Kestrel.Filter;
 using Microsoft.Extensions.Configuration;
@@ -11,11 +12,11 @@ namespace Microsoft.AspNet.Server.Kestrel
 {
     public class KestrelServerInformation : IKestrelServerInformation, IServerAddressesFeature
     {
-        public KestrelServerInformation(IConfiguration configuration, int threadCount)
+        public KestrelServerInformation(IConfiguration configuration)
         {
             Addresses = GetAddresses(configuration);
-            ThreadCount = threadCount;
-            NoDelay = true;
+            ThreadCount = GetThreadCount(configuration);
+            NoDelay = GetNoDelay(configuration);
         }
 
         public ICollection<string> Addresses { get; }
@@ -26,6 +27,32 @@ public KestrelServerInformation(IConfiguration configuration, int threadCount)
 
         public IConnectionFilter ConnectionFilter { get; set; }
 
+        private static int ProcessorThreadCount
+        {
+            get
+            {
+                // Actual core count would be a better number
+                // rather than logical cores which includes hyper-threaded cores.
+                // Divide by 2 for hyper-threading, and good defaults (still need threads to do webserving).
+                var threadCount = Environment.ProcessorCount >> 1;
+
+                if (threadCount < 1)
+                {
+                    // Ensure shifted value is at least one
+                    return 1;
+                }
+
+                if (threadCount > 16)
+                {
+                    // Receive Side Scaling RSS Processor count currently maxes out at 16
+                    // would be better to check the NIC's current hardware queues; but xplat...
+                    return 16;
+                }
+
+                return threadCount;
+            }
+        }
+
         private static ICollection<string> GetAddresses(IConfiguration configuration)
         {
             var addresses = new List<string>();
@@ -39,5 +66,41 @@ private static ICollection<string> GetAddresses(IConfiguration configuration)
 
             return addresses;
         }
+
+        private static int GetThreadCount(IConfiguration configuration)
+        {
+            var threadCountString = configuration["kestrel.threadCount"];
+
+            if (string.IsNullOrEmpty(threadCountString))
+            {
+                return ProcessorThreadCount;
+            }
+
+            int threadCount;
+            if (int.TryParse(threadCountString, NumberStyles.Integer, CultureInfo.InvariantCulture, out threadCount))
+            {
+                return threadCount;
+            }
+
+            return ProcessorThreadCount;
+        }
+
+        private static bool GetNoDelay(IConfiguration configuration)
+        {
+            var noDelayString = configuration["kestrel.noDelay"];
+
+            if (string.IsNullOrEmpty(noDelayString))
+            {
+                return true;
+            }
+
+            bool noDelay;
+            if (bool.TryParse(noDelayString, out noDelay))
+            {
+                return noDelay;
+            }
+
+            return true;
+        }
     }
 }

src/Microsoft.AspNet.Server.Kestrel/ServerFactory.cs

@@ -27,36 +27,11 @@ public ServerFactory(IApplicationLifetime appLifetime, ILoggerFactory loggerFact
 
         public IServer CreateServer(IConfiguration configuration)
         {
-            var threadCount = GetThreadCount();
-            var information = new KestrelServerInformation(configuration, threadCount);
+            var information = new KestrelServerInformation(configuration);
             var serverFeatures = new FeatureCollection();
             serverFeatures.Set<IKestrelServerInformation>(information);
             serverFeatures.Set<IServerAddressesFeature>(information);
             return new KestrelServer(serverFeatures, _appLifetime, _loggerFactory.CreateLogger("Microsoft.AspNet.Server.Kestrel"));
         }
-
-        private static int GetThreadCount()
-        {
-            // Actual core count would be a better number
-            // rather than logical cores which includes hyper-threaded cores.
-            // Divide by 2 for hyper-threading, and good defaults (still need threads to do webserving).
-            // Can be user overriden using IKestrelServerInformation.ThreadCount
-            var threadCount = Environment.ProcessorCount >> 1;
-
-            if (threadCount < 1)
-            {
-                // Ensure shifted value is at least one
-                return 1;
-            }
-
-            if (threadCount > 16)
-            {
-                // Receive Side Scaling RSS Processor count currently maxes out at 16
-                // would be better to check the NIC's current hardware queues; but xplat...
-                return 16;
-            }
-
-            return threadCount;
-        }
     }
 }

test/Microsoft.AspNet.Server.KestrelTests/KestrelServerInformationTests.cs

@@ -0,0 +1,87 @@
+// 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.Collections.Generic;
+using Microsoft.AspNet.Server.Kestrel;
+using Microsoft.Extensions.Configuration;
+using Xunit;
+
+namespace Microsoft.AspNet.Server.KestrelTests
+{
+    public class KestrelServerInformationTests
+    {
+        [Fact]
+        public void SetThreadCountUsingConfiguration()
+        {
+            const int expected = 42;
+
+            var values = new Dictionary<string, string>
+            {
+                { "kestrel.threadCount", expected.ToString() }
+            };
+
+            var configuration = new ConfigurationBuilder()
+                .AddInMemoryCollection(values)
+                .Build();
+
+            var information = new KestrelServerInformation(configuration);
+
+            Assert.Equal(expected, information.ThreadCount);
+        }
+
+        [Fact]
+        public void SetThreadCountUsingProcessorCount()
+        {
+            // Ideally we'd mock Environment.ProcessorCount to test edge cases.
+            var expected = Clamp(Environment.ProcessorCount >> 1, 1, 16);
+
+            var configuration = new ConfigurationBuilder().Build();
+
+            var information = new KestrelServerInformation(configuration);
+
+            Assert.Equal(expected, information.ThreadCount);
+        }
+
+        [Fact]
+        public void SetAddressesUsingConfiguration()
+        {
+            var expected = new List<string> { "http://localhost:1337", "https://localhost:42" };
+
+            var values = new Dictionary<string, string>
+            {
+                { "server.urls", string.Join(";", expected) }
+            };
+
+            var configuration = new ConfigurationBuilder()
+                .AddInMemoryCollection(values)
+                .Build();
+
+            var information = new KestrelServerInformation(configuration);
+
+            Assert.Equal(expected, information.Addresses);
+        }
+
+        [Fact]
+        public void SetNoDelayUsingConfiguration()
+        {
+            var values = new Dictionary<string, string>
+            {
+                { "kestrel.noDelay", "false" }
+            };
+
+            var configuration = new ConfigurationBuilder()
+                .AddInMemoryCollection(values)
+                .Build();
+
+            var information = new KestrelServerInformation(configuration);
+
+            Assert.False(information.NoDelay);
+        }
+
+        private static int Clamp(int value, int min, int max)
+        {
+            return value < min ? min : value > max ? max : value;
+        }
+    }
+}