Fix build performance regression (#84)

martinothamar · Mar 1, 2023 · 30ceab4 · 30ceab4
1 parent 568fdc3
commit 30ceab4
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Showing 3 changed files with 45 additions and 6 deletions.
diff --git a/benchmarks/Mediator.Benchmarks/SourceGenerator/SourceGeneratorBenchmark.cs b/benchmarks/Mediator.Benchmarks/SourceGenerator/SourceGeneratorBenchmark.cs
@@ -1,4 +1,4 @@
-using Mediator.SourceGenerator;
+using Mediator.SourceGenerator;
 using Microsoft.Build.Locator;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
@@ -12,6 +12,7 @@ namespace Mediator.Benchmarks.SourceGenerator;
 [Orderer(SummaryOrderPolicy.FastestToSlowest, MethodOrderPolicy.Declared)]
 [InProcess]
 //[EventPipeProfiler(EventPipeProfile.CpuSampling)]
+//[EtwProfiler]
 //[DisassemblyDiagnoser]
 //[InliningDiagnoser(logFailuresOnly: true, allowedNamespaces: new[] { "Mediator" })]
 public class SourceGeneratorBenchmark
@@ -38,7 +39,7 @@ public void Setup()
 
         var projectFile = Path.Combine(
             currentDirectory,
-            "../../samples/ASPNET_CleanArchitecture/AspNetSample.Api/AspNetSample.Api.csproj"
+            "../../samples/ASPNET_Core_CleanArchitecture/AspNetCoreSample.Api/AspNetCoreSample.Api.csproj"
         );
         if (!File.Exists(projectFile))
             throw new Exception("Project doesnt exist");

diff --git a/benchmarks/README.md b/benchmarks/README.md
@@ -94,3 +94,19 @@ AMD Ryzen 5 5600X, 1 CPU, 12 logical and 6 physical cores
 |     SendStructRequest_MediatR |       Singleton | 594.018 ns | 7.8648 ns | 7.3568 ns | 119.92 |    3.18 |    5 | 0.0839 |   1,416 B |
 
 
+### Source generation
+
+``` ini
+
+BenchmarkDotNet=v0.13.1, OS=Windows 10.0.22621
+AMD Ryzen 5 5600X, 1 CPU, 12 logical and 6 physical cores
+.NET SDK=6.0.202
+  [Host] : .NET 6.0.14 (6.0.1423.7309), X64 RyuJIT
+
+Job=InProcess  Toolchain=InProcessEmitToolchain
+
+```
+|  Method |     Mean |    Error |   StdDev |     Gen 0 |   Gen 1 | Allocated |
+|-------- |---------:|---------:|---------:|----------:|--------:|----------:|
+| Compile | 14.52 ms | 0.249 ms | 0.233 ms | 1406.2500 | 31.2500 |     23 MB |
+
diff --git a/src/Mediator.SourceGenerator.Implementation/Analysis/CompilationAnalyzer.cs b/src/Mediator.SourceGenerator.Implementation/Analysis/CompilationAnalyzer.cs
@@ -311,22 +311,44 @@ private void FindGlobalNamespaces(Queue<INamespaceOrTypeSymbol> queue)
 
         queue.Enqueue(compilation.Assembly.GlobalNamespace);
 
+        var markerSymbol = UnitSymbol;
+        if (markerSymbol is null)
+            throw new Exception("Can't load marker symbol");
+
         foreach (var reference in compilation.References)
         {
             if (compilation.GetAssemblyOrModuleSymbol(reference) is not IAssemblySymbol assemblySymbol)
                 continue;
 
-            if (!assemblySymbol.Modules.Any(IsMediatorLibReferencedByTheModule))
+            if (_symbolComparer.Equals(markerSymbol.ContainingAssembly, assemblySymbol))
+                continue;
+            if (assemblySymbol.Name.StartsWith("Mediator.SourceGenerator", StringComparison.Ordinal))
+                continue;
+
+            if (!assemblySymbol.Modules.Any(static m => IsMediatorLibReferencedByTheModule(m, 0)))
                 continue;
 
             queue.Enqueue(assemblySymbol.GlobalNamespace);
         }
     }
 
-    private static bool IsMediatorLibReferencedByTheModule(IModuleSymbol module)
+    private static bool IsMediatorLibReferencedByTheModule(IModuleSymbol module, int depth)
     {
-        return module.ReferencedAssemblies.Any(ra => ra.Name == Constants.MediatorLib)
-            || module.ReferencedAssemblySymbols.Any(ra => ra.Modules.Any(IsMediatorLibReferencedByTheModule));
+        if (module.ReferencedAssemblies.Any(static ra => ra.Name == Constants.MediatorLib))
+            return true;
+
+        // Above we've checked for direct dependencies on the Mediator.Abstractions package,
+        // but projects can implement Mediator messages using only a transitive dependency
+        // as well.
+        // Even so, going too deep recursively will severely impact build performance
+        // so for now the depth is limited to 3.
+        // This should be solved properly by changing how codegen works..
+        if (depth > 3)
+            return false;
+
+        return module.ReferencedAssemblySymbols.Any(
+            ra => ra.Modules.Any(m => IsMediatorLibReferencedByTheModule(m, depth + 1))
+        );
     }
 
     private void PopulateMetadata(Queue<INamespaceOrTypeSymbol> queue)