[DNM] Performance improvements

Directory.Packages.props

@@ -119,6 +119,7 @@
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="8.0.25" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="8.0.25" />
     <PackageVersion Include="Microsoft.AspNetCore.SignalR.Client" Version="8.0.25" />
+    <PackageVersion Include="Microsoft.AspNetCore.TestHost" Version="8.0.25" />
     <PackageVersion Include="Microsoft.Data.SqlClient" Version="7.0.0" />
     <PackageVersion Include="Microsoft.EntityFrameworkCore.Sqlite" Version="8.0.25" />
     <PackageVersion Include="Microsoft.EntityFrameworkCore.SqlServer" Version="8.0.25" />
@@ -151,11 +152,13 @@
     <PackageVersion Update="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="9.0.14" />
     <PackageVersion Update="Microsoft.AspNetCore.Mvc.Testing" Version="9.0.14" />
     <PackageVersion Update="Microsoft.AspNetCore.SignalR.Client" Version="9.0.14" />
+    <PackageVersion Update="Microsoft.AspNetCore.TestHost" Version="9.0.14" />
   </ItemGroup>
   <ItemGroup Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net10.0'))" Label="Non-production packages, such as for examples and tests, for .NET 10">
     <PackageVersion Update="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="10.0.5" />
     <PackageVersion Update="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.5" />
     <PackageVersion Update="Microsoft.AspNetCore.SignalR.Client" Version="10.0.5" />
+    <PackageVersion Update="Microsoft.AspNetCore.TestHost" Version="10.0.5" />
   </ItemGroup>
 
 </Project>

src/OpenTelemetry.Instrumentation.AspNetCore/AspNetCoreInstrumentation.cs

@@ -19,7 +19,7 @@ internal sealed class AspNetCoreInstrumentation : IDisposable
         "Microsoft.AspNetCore.Hosting.UnhandledException"
     ];
 
-    private readonly Func<string, object?, object?, bool> isEnabled = (eventName, _, _)
+    private readonly Func<string, object?, object?, bool> isEnabled = static (eventName, _, _)
         => DiagnosticSourceEvents.Contains(eventName);
 
     private readonly DiagnosticSourceSubscriber diagnosticSourceSubscriber;
@@ -32,7 +32,5 @@ public AspNetCoreInstrumentation(HttpInListener httpInListener)
 
     /// <inheritdoc/>
     public void Dispose()
-    {
-        this.diagnosticSourceSubscriber?.Dispose();
-    }
+        => this.diagnosticSourceSubscriber?.Dispose();
 }

src/OpenTelemetry.Instrumentation.AspNetCore/AspNetCoreInstrumentationTracerProviderBuilderExtensions.cs

@@ -75,9 +75,7 @@ public static TracerProviderBuilder AddAspNetCoreInstrumentation(
         return builder.AddInstrumentation(sp =>
         {
             var options = sp.GetRequiredService<IOptionsMonitor<AspNetCoreTraceInstrumentationOptions>>().Get(name);
-
-            return new AspNetCoreInstrumentation(
-                new HttpInListener(options));
+            return new AspNetCoreInstrumentation(new HttpInListener(options));
         });
     }
 
@@ -102,9 +100,9 @@ private static void AddAspNetCoreInstrumentationSources(
         string optionsName,
         IServiceProvider? serviceProvider = null)
     {
-        // For .NET7.0 onwards activity will be created using activitySource.
+        // For .NET 7.0+ the activity will be created using activitySource.
         // https://github.com/dotnet/aspnetcore/blob/bf3352f2422bf16fa3ca49021f0e31961ce525eb/src/Hosting/Hosting/src/Internal/HostingApplicationDiagnostics.cs#L327
-        // For .NET6.0 and below, we will continue to use legacy way.
+        // For .NET 6.0 and below, we will continue to use legacy way.
         if (HttpInListener.Net7OrGreater)
         {
             // TODO: Check with .NET team to see if this can be prevented
@@ -122,7 +120,7 @@ private static void AddAspNetCoreInstrumentationSources(
         }
         else
         {
-            builder.AddSource(HttpInListener.ActivitySourceName);
+            builder.AddSource(HttpInListener.ActivitySource.Name);
             builder.AddLegacySource(HttpInListener.ActivityOperationName); // for the activities created by AspNetCore
         }
 

src/OpenTelemetry.Instrumentation.AspNetCore/CHANGELOG.md

@@ -11,6 +11,15 @@
 * Updated OpenTelemetry core component version(s) to `1.15.2`.
   ([#4080](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4080))
 
+* Avoid duplicative work to add tags to traces when they are already natively supported
+  by ASP.NET Core itself. When using ASP.NET Core 10, performance can be
+  improved by setting the `Microsoft.AspNetCore.Hosting.SuppressActivityOpenTelemetryData`
+  AppContext switch to `false` (its default value is `true`).
+  ([#3993](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/3993))
+
+* Add instrumentation schema URL to traces for `netstandard2.0`.
+  ([#4066](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4066))
+
 ## 1.15.1
 
 Released 2026-Mar-11