Add caching for type lookup of runtime class name, to address excepti…

…on storm perf issue (#828)
microsoft · Apr 28, 2021 · ef2472e · ef2472e
1 parent da45411
commit ef2472e
Show file tree

Hide file tree

Showing 2 changed files with 26 additions and 14 deletions.
diff --git a/src/WinRT.Runtime/ComWrappersSupport.cs b/src/WinRT.Runtime/ComWrappersSupport.cs
@@ -264,13 +264,8 @@ internal static Func<IInspectable, object> CreateTypedRcwFactory(string runtimeC
                 return (IInspectable obj) => new ABI.System.Nullable<Type>(obj.ObjRef);
             }
 
-            Type implementationType = null;
-
-            try
-            {
-                (implementationType, _) = TypeNameSupport.FindTypeByName(runtimeClassName.AsSpan());
-            }
-            catch (TypeLoadException)
+            Type implementationType = TypeNameSupport.FindTypeByNameCached(runtimeClassName);
+            if(implementationType == null)
             {
                 // If we reach here, then we couldn't find a type that matches the runtime class name.
                 // Fall back to using IInspectable directly.
@@ -318,13 +313,7 @@ internal static string GetRuntimeClassForTypeCreation(IInspectable inspectable,
                 Type implementationType = null;
                 if (!string.IsNullOrEmpty(runtimeClassName))
                 {
-                    try
-                    {
-                        (implementationType, _) = TypeNameSupport.FindTypeByName(runtimeClassName.AsSpan());
-                    }
-                    catch (TypeLoadException)
-                    {
-                    }
+                    implementationType = TypeNameSupport.FindTypeByNameCached(runtimeClassName);
                 }
 
                 if (!(implementationType != null &&

diff --git a/src/WinRT.Runtime/TypeNameSupport.cs b/src/WinRT.Runtime/TypeNameSupport.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
@@ -25,12 +26,34 @@ enum TypeNameGenerationFlags
     static class TypeNameSupport
     {
         private static List<Assembly> projectionAssemblies = new List<Assembly>();
+        private static ConcurrentDictionary<string, Type> typeNameCache = new ConcurrentDictionary<string, Type>() { ["TrackerCollection<T>"] = null };
 
         public static void RegisterProjectionAssembly(Assembly assembly)
         {
             projectionAssemblies.Add(assembly);
         }
 
+        /// <summary>
+        /// Parses and loads the given type name, if not found in the cache.
+        /// </summary>
+        /// <param name="runtimeClassName">The runtime class name to attempt to parse.</param>
+        /// <returns>The type, if found.  Null otherwise</returns>
+        public static Type FindTypeByNameCached(string runtimeClassName)
+        {
+            return typeNameCache.GetOrAdd(runtimeClassName, (runtimeClassName) =>
+            {
+                Type implementationType = null;
+                try
+                {
+                    implementationType = FindTypeByName(runtimeClassName.AsSpan()).type;
+                }
+                catch (Exception)
+                {
+                }
+                return implementationType;
+            });
+        }
+
         /// <summary>
         /// Parse the first full type name within the provided span.
         /// </summary>