Performance optimizations

Frameworks/MQTTnet.AspnetCore/MQTTnet.AspnetCore.csproj

@@ -6,6 +6,10 @@
     <FileVersion>2.5.2.0</FileVersion>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
+    <DefineConstants>RELEASE;NETSTANDARD2_0</DefineConstants>
+  </PropertyGroup>
+
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.WebSockets" Version="2.0.0" />

Frameworks/MQTTnet.NetStandard/Adapter/MqttChannelAdapter.cs

@@ -31,23 +31,23 @@ namespace MQTTnet.Adapter
 
         public IMqttPacketSerializer PacketSerializer { get; }
 
-        public async Task ConnectAsync(TimeSpan timeout)
+        public Task ConnectAsync(TimeSpan timeout)
         {
             _logger.Info<MqttChannelAdapter>("Connecting [Timeout={0}]", timeout);
 
-            await ExecuteAndWrapExceptionAsync(() => _channel.ConnectAsync().TimeoutAfter(timeout));
+            return ExecuteAndWrapExceptionAsync(() => _channel.ConnectAsync().TimeoutAfter(timeout));
         }
 
-        public async Task DisconnectAsync(TimeSpan timeout)
+        public Task DisconnectAsync(TimeSpan timeout)
         {
             _logger.Info<MqttChannelAdapter>("Disconnecting [Timeout={0}]", timeout);
 
-            await ExecuteAndWrapExceptionAsync(() => _channel.DisconnectAsync().TimeoutAfter(timeout));
+            return ExecuteAndWrapExceptionAsync(() => _channel.DisconnectAsync().TimeoutAfter(timeout));
         }
 
-        public async Task SendPacketsAsync(TimeSpan timeout, CancellationToken cancellationToken, IEnumerable<MqttBasePacket> packets)
+        public Task SendPacketsAsync(TimeSpan timeout, CancellationToken cancellationToken, IEnumerable<MqttBasePacket> packets)
         {
-            await ExecuteAndWrapExceptionAsync(async () =>
+            return ExecuteAndWrapExceptionAsync(async () =>
             {
                 await _semaphore.WaitAsync(cancellationToken).ConfigureAwait(false);
                 try

Frameworks/MQTTnet.NetStandard/Internal/TaskExtensions.cs

@@ -9,13 +9,15 @@ namespace MQTTnet.Internal
     {
         public static async Task TimeoutAfter(this Task task, TimeSpan timeout)
         {
-            using (var cancellationTokenSource = new CancellationTokenSource())
+            if (task == null) throw new ArgumentNullException(nameof(task));
+
+            using (var timeoutCts = new CancellationTokenSource())
             {
                 try
                 {
-                    var timeoutTask = Task.Delay(timeout, cancellationTokenSource.Token);
+                    var timeoutTask = Task.Delay(timeout, timeoutCts.Token);
                     var finishedTask = await Task.WhenAny(timeoutTask, task).ConfigureAwait(false);
-
+                    
                     if (finishedTask == timeoutTask)
                     {
                         throw new MqttCommunicationTimedOutException();
@@ -33,18 +35,20 @@ namespace MQTTnet.Internal
                 }
                 finally
                 {
-                    cancellationTokenSource.Cancel();
+                    timeoutCts.Cancel();
                 }
             }
         }
 
         public static async Task<TResult> TimeoutAfter<TResult>(this Task<TResult> task, TimeSpan timeout)
         {
-            using (var cancellationTokenSource = new CancellationTokenSource())
+            if (task == null) throw new ArgumentNullException(nameof(task));
+
+            using (var timeoutCts = new CancellationTokenSource())
             {
                 try
                 {
-                    var timeoutTask = Task.Delay(timeout, cancellationTokenSource.Token);
+                    var timeoutTask = Task.Delay(timeout, timeoutCts.Token);
                     var finishedTask = await Task.WhenAny(timeoutTask, task).ConfigureAwait(false);
 
                     if (finishedTask == timeoutTask)
@@ -66,7 +70,7 @@ namespace MQTTnet.Internal
                 }
                 finally
                 {
-                    cancellationTokenSource.Cancel();
+                    timeoutCts.Cancel();
                 }
             }
         }

Frameworks/MQTTnet.NetStandard/MQTTnet.Netstandard.csproj

@@ -36,6 +36,10 @@
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" />
 
+  <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|netstandard1.3|AnyCPU'">
+    <DefineConstants>RELEASE;NETSTANDARD1_3</DefineConstants>
+  </PropertyGroup>
+
   <ItemGroup Condition="'$(TargetFramework)'=='netstandard2.0'">
     <PackageReference Include="System.Net.Security" Version="4.3.2" />
     <PackageReference Include="System.Net.WebSockets" Version="4.3.0" />

Frameworks/MQTTnet.NetStandard/Server/MqttClientSession.cs

@@ -143,14 +143,14 @@ namespace MQTTnet.Server
 
         private Task ProcessReceivedPacketAsync(IMqttChannelAdapter adapter, MqttBasePacket packet, CancellationToken cancellationToken)
         {
-            if (packet is MqttPingReqPacket)
+            if (packet is MqttPublishPacket publishPacket)
             {
-                return adapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, cancellationToken, new MqttPingRespPacket());
+                return HandleIncomingPublishPacketAsync(adapter, publishPacket, cancellationToken);
             }
 
-            if (packet is MqttPublishPacket publishPacket)
+            if (packet is MqttPingReqPacket)
             {
-                return HandleIncomingPublishPacketAsync(adapter, publishPacket, cancellationToken);
+                return adapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, cancellationToken, new MqttPingRespPacket());
             }
 
             if (packet is MqttPubRelPacket pubRelPacket)

Frameworks/MQTTnet.NetStandard/Server/MqttClientSessionsManager.cs

@@ -168,7 +168,7 @@ namespace MQTTnet.Server
 
             lock (_sessions)
             {
-                foreach (var clientSession in _sessions.Values.ToList())
+                foreach (var clientSession in _sessions.Values)
                 {
                     clientSession.EnqueueApplicationMessage(applicationMessage);
                 }

README.md

@@ -18,7 +18,7 @@ MQTTnet is a high performance .NET library for MQTT based communication. It prov
 * TLS 1.2 support for client and server (but not UWP servers)
 * Extensible communication channels (i.e. In-Memory, TCP, TCP+TLS, WS)
 * Lightweight (only the low level implementation of MQTT, no overhead)
-* Performance optimized (processing ~27.000 messages / second)*
+* Performance optimized (processing ~30.000 messages / second)*
 * Interfaces included for mocking and testing
 * Access to internal trace messages
 * Unit tested (70+ tests)

Tests/MQTTnet.TestApp.NetCore/PerformanceTest.cs

@@ -43,33 +43,6 @@ namespace MQTTnet.TestApp.NetCore
 
                 var client = new MqttFactory().CreateMqttClient();
 
-                client.Connected += async (s, e) =>
-                {
-                    Console.WriteLine("### CONNECTED WITH SERVER ###");
-
-                    await client.SubscribeAsync(new List<TopicFilter>
-                    {
-                        new TopicFilter("#")
-                    });
-
-                    Console.WriteLine("### SUBSCRIBED ###");
-                };
-
-                client.Disconnected += async (s, e) =>
-                {
-                    Console.WriteLine("### DISCONNECTED FROM SERVER ###");
-                    await Task.Delay(TimeSpan.FromSeconds(5));
-
-                    try
-                    {
-                        await client.ConnectAsync(options);
-                    }
-                    catch
-                    {
-                        Console.WriteLine("### RECONNECTING FAILED ###");
-                    }
-                };
-
                 try
                 {
                     await client.ConnectAsync(options);
@@ -79,24 +52,12 @@ namespace MQTTnet.TestApp.NetCore
                     Console.WriteLine("### CONNECTING FAILED ###" + Environment.NewLine + exception);
                 }
 
-                Console.WriteLine("### WAITING FOR APPLICATION MESSAGES ###");
-
-                var testMessageCount = 10000;
                 var message = CreateMessage();
-                var stopwatch = Stopwatch.StartNew();
-                for (var i = 0; i < testMessageCount; i++)
-                {
-                    await client.PublishAsync(message);
-                }
-
-                stopwatch.Stop();
-                Console.WriteLine($"Sent 10.000 messages within {stopwatch.ElapsedMilliseconds} ms ({stopwatch.ElapsedMilliseconds / (float)testMessageCount} ms / message).");
-
                 var messages = new[] { message };
-                var sentMessagesCount = 0;
 
-                stopwatch.Restart();
+                var stopwatch = Stopwatch.StartNew();
 
+                var sentMessagesCount = 0;
                 while (stopwatch.ElapsedMilliseconds < 1000)
                 {
                     await client.PublishAsync(messages).ConfigureAwait(false);
@@ -104,6 +65,17 @@ namespace MQTTnet.TestApp.NetCore
                 }
 
                 Console.WriteLine($"Sending {sentMessagesCount} messages per second.");
+                
+                stopwatch.Restart();
+
+                var testMessageCount = 10000;
+                for (var i = 0; i < testMessageCount; i++)
+                {
+                    await client.PublishAsync(message);
+                }
+
+                stopwatch.Stop();
+                Console.WriteLine($"Sent 10.000 messages within {stopwatch.ElapsedMilliseconds} ms ({stopwatch.ElapsedMilliseconds / (float)testMessageCount} ms / message).");
 
                 var last = DateTime.Now;
                 var msgCount = 0;