[v2] Add Diagnostics Metrics Tracking to MAUI Applications

src/Controls/samples/Controls.Sample/MauiProgram.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.Metrics;
+using System.Runtime.CompilerServices;
 using Maui.Controls.Sample.Controls;
 using Maui.Controls.Sample.Pages;
 using Maui.Controls.Sample.Services;
@@ -69,20 +71,47 @@ public static MauiApp CreateMauiApp()
 #endif
 			}
 
+
+			appBuilder.Services.AddMetrics();
+			ActivitySource.AddActivityListener(new ActivityListener
+			{
+				ShouldListenTo = source => true,
+				Sample = (ref ActivityCreationOptions<ActivityContext> options) => ActivitySamplingResult.AllDataAndRecorded,
+				ActivityStarted = activity => Console.WriteLine("Started: {0,-15} {1,-60}", activity.OperationName, activity.Id),
+				ActivityStopped = activity => Console.WriteLine("Stopped: {0,-15} {1,-60} {2,-15}", activity.OperationName, activity.Id, activity.Duration)
+			});
+
+			MeterListener meterListener = new();
+			meterListener.InstrumentPublished = (instrument, listener) =>
+			{
+				if (instrument.Meter.Name is "Microsoft.Maui.Diagnostics")
+				{
+					listener.EnableMeasurementEvents(instrument);
+				}
+			};
+
+			meterListener.SetMeasurementEventCallback<int>((Instrument instrument, int measurement, ReadOnlySpan<KeyValuePair<string, object?>> tags, object? state) =>
+			{
+				Console.WriteLine($"{instrument.Name} recorded measurement {measurement}");
+			});
+			// Start the meterListener, enabling InstrumentPublished callbacks.
+			meterListener.Start();
+
+
 			if (UseMauiGraphicsSkia)
 			{
 				/*
 				appBuilder.ConfigureMauiHandlers(handlers =>
 				{
 					handlers.AddHandler<GraphicsView, SkiaGraphicsViewHandler>();
 					handlers.AddHandler<BoxView, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Ellipse, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Line, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Path, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Polygon, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Polyline, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Rectangle, SkiaShapeViewHandler>();
-					handlers.AddHandler<Microsoft.Maui.Controls.Shapes.RoundRectangle, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Ellipse, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Line, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Path, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Polygon, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Polyline, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.Rectangle, SkiaShapeViewHandler>();
+				handlers.AddHandler<Microsoft.Maui.Controls.Shapes.RoundRectangle, SkiaShapeViewHandler>();
 				});
 				*/
 			}

src/Controls/src/Core/Diagnostics/MetricsTracker.cs

@@ -0,0 +1,70 @@
+using System;
+using System.Diagnostics;
+using Microsoft.Maui.Diagnostics;
+
+namespace Microsoft.Maui.Controls.Diagnostics;
+
+enum DiagnosticsMeasuring
+{
+    None,
+    Measure,
+    Arrange
+}
+
+readonly struct MetricsTracker : IDisposable
+{
+    readonly Activity? _activity;
+    readonly IView _view;
+    readonly DiagnosticsMeasuring _activityName;
+
+    public static MetricsTracker? Create(IView view, DiagnosticsMeasuring diagnosticsMeasuring)
+    {
+        if (RuntimeFeature.IsMeterSupported)
+            return new MetricsTracker(view, diagnosticsMeasuring);
+
+        return null;
+    }
+
+    MetricsTracker(IView view, DiagnosticsMeasuring diagnosticsMeasuring)
+    {
+        _view = view;
+        _activity = view.StartActivity($"{diagnosticsMeasuring}");
+        _activityName = diagnosticsMeasuring;
+
+        if (_activity is null)
+            return;
+
+        if (view is Element element)
+        {
+            _activity.SetTag("element.id", element.Id);
+            _activity.SetTag("element.automation_id", element.AutomationId);
+            _activity.SetTag("element.class_id", element.ClassId);
+            _activity.SetTag("element.style_id", element.StyleId);
+        }
+
+        if (view is VisualElement ve)
+        {
+            _activity.SetTag("element.class", ve.@class);
+            _activity.SetTag("element.frame", ve.Frame);
+        }
+    }
+
+    public void Dispose()
+    {
+        _activity?.Stop();
+
+        switch (_activityName)
+        {
+            case DiagnosticsMeasuring.Arrange:
+                _view.RecordArrange(_activity?.Duration);
+                break;
+            case DiagnosticsMeasuring.Measure:
+                _view.RecordMeasure(_activity?.Duration);
+                break;
+            default:
+                break;
+        }
+
+        _activity?.Dispose();
+    }
+}

src/Controls/src/Core/VisualElement/VisualElement.cs

@@ -4,9 +4,10 @@
 using System.ComponentModel;
 using System.Diagnostics;
 using System.Globalization;
+using Microsoft.Maui.Controls.Diagnostics;
 using Microsoft.Maui.Controls.Internals;
 using Microsoft.Maui.Controls.Shapes;
-
+using Microsoft.Maui.Diagnostics;
 using Microsoft.Maui.Graphics;
 using Microsoft.Maui.Layouts;
 using Geometry = Microsoft.Maui.Controls.Shapes.Geometry;
@@ -1888,11 +1889,12 @@ public int ZIndex
 		public void Arrange(Rect bounds)
 		{
 			ArrangeOverride(bounds);
-		}
+		}		
 
 		/// <inheritdoc/>
 		Size IView.Arrange(Rect bounds)
 		{
+			using var activity = MetricsTracker.Create(this, DiagnosticsMeasuring.Arrange);
 			return ArrangeOverride(bounds);
 		}
 
@@ -1947,6 +1949,7 @@ void IView.InvalidateArrange()
 		/// <inheritdoc/>
 		Size IView.Measure(double widthConstraint, double heightConstraint)
 		{
+			using var activity = MetricsTracker.Create(this, DiagnosticsMeasuring.Measure);
 			DesiredSize = MeasureOverride(widthConstraint, heightConstraint);
 			return DesiredSize;
 		}

src/Core/src/Diagnostics/MauiDiagnostics.cs

@@ -0,0 +1,89 @@
+using System;
+using System.Diagnostics;
+using System.Diagnostics.Metrics;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Maui.Hosting;
+
+namespace Microsoft.Maui.Diagnostics;
+
+internal class MauiDiagnostics
+{
+    public MauiDiagnostics(IMeterFactory? meterFactory = null)
+    {
+        ActivitySource = new ActivitySource("Microsoft.Maui.Diagnostics", "1.0.0");
+
+        Meters = meterFactory?.Create("Microsoft.Maui.Diagnostics", "1.0.0");
+
+        MeasureCounter = Meters?.CreateCounter<int>("maui.layout.measure_count", "{times}", "The number of times a measure happened.");
+        ArrangeCounter = Meters?.CreateCounter<int>("maui.layout.arrange_count", "{times}", "The number of times an arrange happened.");
+
+        MeasureHistogram = Meters?.CreateHistogram<int>("maui.layout.measure_duration", "ns");
+        ArrangeHistogram = Meters?.CreateHistogram<int>("maui.layout.arrange_duration", "ns");
+    }
+
+	public ActivitySource ActivitySource { get; }
+	public Meter? Meters { get; }
+	public Counter<int>? MeasureCounter { get; }
+	public Counter<int>? ArrangeCounter { get; }
+	public Histogram<int>? MeasureHistogram { get; }
+	public Histogram<int>? ArrangeHistogram { get; }
+}
+
+internal static class MauiDiagnosticsExtensions
+{
+	public static MauiAppBuilder ConfigureMauiDiagnostics(this MauiAppBuilder builder)
+	{
+        if (RuntimeFeature.IsMeterSupported)
+        {
+            builder.Services.AddSingleton(serviceProvider => new MauiDiagnostics(serviceProvider.GetService<IMeterFactory>()));
+        }
+
+		return builder;
+	}
+
+	static MauiDiagnostics? GetMauiDiagnostics(this IView view)
+	{
+        if (!RuntimeFeature.IsMeterSupported)
+            return null;
+
+		return view.Handler?.MauiContext?.Services.GetService<MauiDiagnostics>();
+	}
+
+	public static Activity? StartActivity(this IView view, string name)
+	{
+        if (!RuntimeFeature.IsMeterSupported)
+            return null;
+
+		var elementName = view.GetType().Name;
+
+		var activity = view.GetMauiDiagnostics()?.ActivitySource.StartActivity($"{name} {elementName}");
+
+		activity?.SetTag("element.type", view.GetType().FullName);
+
+		return activity;
+	}
+
+	public static void RecordMeasure(this IView view, TimeSpan? duration)
+	{
+        if (!RuntimeFeature.IsMeterSupported)
+            return;
+
+		var diag = view.GetMauiDiagnostics();
+		diag?.MeasureCounter?.Add(1);
+
+        if (duration is not null)
+		    diag?.MeasureHistogram?.Record((int)duration.Value.TotalNanoseconds);
+	}
+
+	public static void RecordArrange(this IView view, TimeSpan? duration)
+	{
+        if (!RuntimeFeature.IsMeterSupported)
+            return;
+
+		var diag = view.GetMauiDiagnostics();
+		diag?.ArrangeCounter?.Add(1);
+
+		if (duration is not null)
+            diag?.ArrangeHistogram?.Record((int)duration.Value.TotalNanoseconds);
+	}
+}

src/Core/src/Hosting/MauiAppBuilder.cs

@@ -7,6 +7,7 @@
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
+using Microsoft.Maui.Diagnostics;
 using Microsoft.Maui.LifecycleEvents;
 
 namespace Microsoft.Maui.Hosting
@@ -53,6 +54,7 @@ internal MauiAppBuilder(bool useDefaults)
 				this.ConfigureWindowEvents();
 				this.ConfigureDispatching();
 				this.ConfigureEnvironmentVariables();
+				this.ConfigureMauiDiagnostics();
 
 				this.UseEssentials();
 

src/Core/src/RuntimeFeature.cs

@@ -25,6 +25,7 @@ static class RuntimeFeature
 		const bool IsHybridWebViewSupportedByDefault = true;
 		const bool SupportNamescopesByDefault = true;
 		const bool EnableDiagnosticsByDefault = false;
+		const bool IsMeterSupportedByDefault = true;
 
 #pragma warning disable IL4000 // Return value does not match FeatureGuardAttribute 'System.Diagnostics.CodeAnalysis.RequiresUnreferencedCodeAttribute'. 
 #if NET9_0_OR_GREATER
@@ -102,6 +103,16 @@ public static bool AreNamescopesSupported
 
 		}
 
+		// https://github.com/dotnet/runtime/blob/8c7de742a77ed3919a3f3fe8c4475fce689f5e83/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs#L291-L295
+#if NET9_0_OR_GREATER
+		[FeatureSwitchDefinition($"System.Diagnostics.Metrics.Meter.IsSupported")]
+#endif
+		public static bool IsMeterSupported => AppContext.TryGetSwitch($"System.Diagnostics.Metrics.Meter.IsSupported", out bool isEnabled)
+				? isEnabled
+				: IsMeterSupportedByDefault;
+
+
+
 #if NET9_0_OR_GREATER
 		[FeatureSwitchDefinition($"{FeatureSwitchPrefix}.{nameof(EnableDiagnostics)}")]
 #endif