Improve string builder caches

src/Build.OM.UnitTests/Microsoft.Build.Engine.OM.UnitTests.csproj

@@ -77,9 +77,6 @@
     <Compile Include="..\Shared\FileUtilitiesRegex.cs">
       <ExcludeFromStyleCop>true</ExcludeFromStyleCop>
     </Compile>
-    <Compile Include="..\Shared\StringBuilderCache.cs">
-      <ExcludeFromStyleCop>True</ExcludeFromStyleCop>
-    </Compile>
     <Compile Include="..\Shared\ExceptionHandling.cs">
       <ExcludeFromStyleCop>true</ExcludeFromStyleCop>
     </Compile>

src/Build/Microsoft.Build.csproj

@@ -99,9 +99,6 @@
     <Compile Include="..\Shared\ReadOnlyEmptyCollection.cs">
       <Link>Collections\ReadOnlyEmptyCollection.cs</Link>
     </Compile>
-    <Compile Include="..\Shared\StringBuilderCache.cs">
-      <ExcludeFromStyleCop>True</ExcludeFromStyleCop>
-    </Compile>
     <Compile Include="..\Shared\BufferedReadStream.cs" />
     <Compile Include="..\Shared\TaskHostConfiguration.cs" />
     <Compile Include="..\Shared\TaskHostTaskCancelled.cs" />
@@ -140,7 +137,6 @@
     <Compile Include="..\Shared\TaskEngineAssemblyResolver.cs">
       <ExcludeFromStyleCop>true</ExcludeFromStyleCop>
     </Compile>
-    <Compile Include="..\Shared\ReuseableStringBuilder.cs" />
     <Compile Include="..\Shared\ThreadPoolExtensions.cs" />
     <Compile Include="AssemblyInfo.cs" />
     <Compile Include="BackEnd\BuildManager\BuildManager.cs" />

src/Framework.UnitTests/Microsoft.Build.Framework.UnitTests.csproj

@@ -41,7 +41,6 @@
     <Compile Include="..\Shared\BuildEnvironmentHelper.cs" />
     <Compile Include="..\Shared\ResourceUtilities.cs" />
     <Compile Include="..\Shared\ExceptionHandling.cs" />
-    <Compile Include="..\Shared\StringBuilderCache.cs" />
     <Compile Include="..\Shared\FileUtilitiesRegex.cs" />
     <Compile Include="..\Shared\UnitTests\AssemblyResources.cs" />
   </ItemGroup>

src/Framework/MSBuildEventSource.cs

@@ -490,6 +490,35 @@ public void CachedSdkResolverServiceResolveSdkStop(string sdkName, string soluti
             WriteEvent(67, sdkName, solutionPath, projectPath, success);
         }
 
-        #endregion
+        /// <remarks>
+        /// This events are quite frequent so they are collected by Debug binaries only.
+        /// </remarks>
+        [Event(68, Keywords = Keywords.All)]
+        public void ReusableStringBuilderFactoryStart(int hash, int newCapacity, int oldCapacity, string type)
+        {
+            WriteEvent(68, hash, newCapacity, oldCapacity, type);
+        }
+
+        /// <remarks>
+        /// This events are quite frequent so they are collected by Debug binaries only.
+        /// </remarks>
+        [Event(69, Keywords = Keywords.All)]
+        public void ReusableStringBuilderFactoryStop(int hash, int returningCapacity, int returningLength, string type)
+        {
+            WriteEvent(69, hash, returningCapacity, returningLength, type);
+        }
+
+        /// <remarks>
+        /// As oppose to other ReusableStringBuilderFactory events this one is expected to happens very un-frequently
+        ///    and if it is seen more than 100x per build it might indicates wrong usage patterns resulting into degrading
+        ///    efficiency of ReusableStringBuilderFactory. Hence it is collected in release build as well.
+        /// </remarks>
+        [Event(70, Keywords = Keywords.All)]
+        public void ReusableStringBuilderFactoryUnbalanced(int oldHash, int newHash)
+        {
+            WriteEvent(70, oldHash, newHash);
+        }
+
+#endregion
     }
 }