[browser] reduce msbuild memory footprint

eng/testing/tests.browser.targets

@@ -207,6 +207,8 @@
     </ItemGroup>
 
     <WriteLinesToFile File="$(WasmMainHtmlPath)" Lines="&lt;html&gt;&lt;body&gt;&lt;script type='module' src='$(WasmMainJSFileName)'&gt;&lt;/script&gt;&lt;/body&gt;&lt;/html&gt;" Overwrite="True" Condition="!Exists('$(WasmMainHtmlPath)')"/>
+
+    <ForceMSBuildGC />
   </Target>
 
   <Target Name="_PrepareForAOTOnHelix">

eng/testing/tests.wasi.targets

@@ -129,6 +129,8 @@
               TargetPath="%(WasmFilesToIncludeFromPublishDir.Identity)"
               Condition="'%(WasmFilesToIncludeFromPublishDir.Identity)' != ''" />
     </ItemGroup>
+
+    <ForceMSBuildGC />
   </Target>
 
   <Target Name="_PrepareForAOTOnHelix">

eng/testing/tests.wasm.targets

@@ -91,7 +91,9 @@
 
   <UsingTask Condition="'$(BuildAOTTestsOnHelix)' == 'true'"
              TaskName="Microsoft.WebAssembly.Build.Tasks.GenerateAOTProps"
-             AssemblyFile="$(WasmBuildTasksAssemblyPath)" />
+             AssemblyFile="$(WasmBuildTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.ForceMSBuildGC" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
 
   <Target Name="_BundleAOTTestWasmAppForHelix" DependsOnTargets="$(_BundleAOTTestWasmAppForHelixDependsOn)">
     <PropertyGroup>

src/mono/browser/browser.proj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.Build.NoTargets">
 
-  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.RunWithEmSdkEnv" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.RunWithEmSdkEnv" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <PropertyGroup>
     <!-- FIXME: clean up the duplication with libraries Directory.Build.props -->
@@ -49,7 +49,7 @@
     <PackageReference Include="System.Runtime.TimeZoneData" PrivateAssets="all" Version="$(SystemRuntimeTimeZoneDataVersion)" GeneratePathProperty="true" />
   </ItemGroup>
 
-  <UsingTask TaskName="ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
+  <UsingTask TaskName="ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
   <Target Name="GenerateManagedToNative" DependsOnTargets="CheckEnv;ResolveLibrariesFromLocalBuild">
     <PropertyGroup>
       <WasmPInvokeTablePath>$(WasmObjDir)\pinvoke-table.h</WasmPInvokeTablePath>
@@ -81,7 +81,7 @@
     </ManagedToNativeGenerator>
   </Target>
 
-  <UsingTask TaskName="EmitBundleSourceFiles" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
+  <UsingTask TaskName="EmitBundleSourceFiles" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
   <Target Name="GenerateTimezonesArchive" Returns="@(_WasmArchivedTimezones)" Condition="'$(InvariantTimezone)' != 'true'">
     <PropertyGroup>
       <_WasmTimezonesPath>$([MSBuild]::NormalizePath('$(PkgSystem_Runtime_TimeZoneData)', 'contentFiles', 'any', 'any', 'data'))</_WasmTimezonesPath>

src/mono/browser/build/BrowserWasmApp.targets

@@ -7,7 +7,7 @@
 
   <Import Project="$(WasmCommonTargetsPath)WasmApp.Common.targets" />
 
-  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.WasmAppBuilder" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.WasmAppBuilder" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <PropertyGroup>
     <PrepareForWasmBuildNativeDependsOn>

src/mono/browser/build/WasmApp.InTree.targets

@@ -1,8 +1,8 @@
 <Project>
   <!-- This depends on the root Directory.Build.targets imported this file -->
-  <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" />
-  <UsingTask TaskName="ILStrip" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
-  <UsingTask TaskName="RuntimeConfigParserTask" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
+  <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="ILStrip" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="RuntimeConfigParserTask" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <!-- TODO: this breaks runtime tests on Helix due to the file not being there for some reason. Once this is fixed we can remove the UpdateRuntimePack target here -->
   <Import Project="$(RepositoryEngineeringDir)targetingpacks.targets" Condition="'$(TargetingpacksTargetsImported)' != 'true' and '$(ImportTargetingPacksTargetsInWasmAppTargets)' == 'true'"/>

src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.targets

@@ -54,10 +54,10 @@ Copyright (c) .NET Foundation. All rights reserved.
     <DisableBuildCompression Condition="'$(WasmBuildingForNestedPublish)' == 'true'">true</DisableBuildCompression>
   </PropertyGroup>
 
-  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.GenerateWasmBootJson" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" />
-  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.ComputeWasmBuildAssets" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" />
-  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.ComputeWasmPublishAssets" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" />
-  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.ConvertDllsToWebCil" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" />
+  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.GenerateWasmBootJson" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.ComputeWasmBuildAssets" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.ComputeWasmPublishAssets" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.NET.Sdk.WebAssembly.ConvertDllsToWebCil" AssemblyFile="$(_WebAssemblySdkTasksAssembly)" TaskFactory="TaskHostFactory" />
 
   <PropertyGroup>
     <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>

src/mono/sample/Directory.Build.targets

@@ -1,5 +1,5 @@
 <Project>
-  <UsingTask TaskName="GenerateRunScript" AssemblyFile="$(InstallerTasksAssemblyPath)"/>
+  <UsingTask TaskName="GenerateRunScript" AssemblyFile="$(InstallerTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <PropertyGroup>
     <RunScriptOutputName Condition="'$(TargetOS)' != 'windows'">RunTests.sh</RunScriptOutputName>

src/mono/wasm/build/WasmApp.Common.targets

@@ -105,12 +105,12 @@
       - @(EmccExportedFunction)      - Extra function for emcc flag EXPORTED_FUNCTIONS
   -->
 
-  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.WasmLoadAssembliesAndReferences" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
-  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
-  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.EmccCompile" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
-  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.WasmCalculateInitialHeapSize" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
-  <UsingTask TaskName="MonoTargetsTasks.MarshalingPInvokeScanner" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
-  <UsingTask TaskName="EmitBundleObjectFiles" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.WasmLoadAssembliesAndReferences" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.EmccCompile" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.WasmCalculateInitialHeapSize" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="MonoTargetsTasks.MarshalingPInvokeScanner" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="EmitBundleObjectFiles" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <PropertyGroup>
     <PrepareInputsForWasmBuildDependsOn>

src/mono/wasm/build/WasmApp.LocalBuild.targets

@@ -22,9 +22,9 @@
 <Project>
   <Import Project="$(_WasmTargetsDir)$(_TargetsBaseName).targets" />
 
-  <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" />
-  <UsingTask TaskName="ILStrip" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
-  <UsingTask TaskName="RuntimeConfigParserTask" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
+  <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="ILStrip" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="RuntimeConfigParserTask" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <PropertyGroup>
     <PublishTrimmed Condition="'$(PublishTrimmed)' == ''">true</PublishTrimmed>

src/tasks/AotCompilerTask/MonoAOTCompiler.cs

@@ -542,8 +542,16 @@ private bool ExecuteInternal()
         {
             int allowedParallelism = DisableParallelAot ? 1 : Math.Min(_assembliesToCompile.Count, Environment.ProcessorCount);
             IBuildEngine9? be9 = BuildEngine as IBuildEngine9;
-            if (be9 is not null)
-                allowedParallelism = be9.RequestCores(allowedParallelism);
+            try
+            {
+                if (be9 is not null)
+                    allowedParallelism = be9.RequestCores(allowedParallelism);
+            }
+            catch(NotImplementedException)
+            {
+                // RequestCores is not implemented in TaskHostFactory
+                be9 = null;
+            }
 
             /*
                 From: https://github.com/dotnet/runtime/issues/46146#issuecomment-754021690

src/tasks/MonoTargetsTasks/EmitBundleTask/EmitBundleBase.cs

@@ -155,8 +155,16 @@ public override bool Execute()
         // Generate source file(s) containing each resource's byte data and size
         int allowedParallelism = Math.Max(Math.Min(bundledResources.Count, Environment.ProcessorCount), 1);
         IBuildEngine9? be9 = BuildEngine as IBuildEngine9;
-        if (be9 is not null)
-            allowedParallelism = be9.RequestCores(allowedParallelism);
+        try
+        {
+            if (be9 is not null)
+                allowedParallelism = be9.RequestCores(allowedParallelism);
+        }
+        catch(NotImplementedException)
+        {
+            // RequestCores is not implemented in TaskHostFactory
+            be9 = null;
+        }
 
         try
         {

src/tasks/MonoTargetsTasks/ILStrip/ILStrip.cs

@@ -76,8 +76,17 @@ public override bool Execute()
 
         int allowedParallelism = DisableParallelStripping ? 1 : Math.Min(Assemblies.Length, Environment.ProcessorCount);
         IBuildEngine9? be9 = BuildEngine as IBuildEngine9;
-        if (be9 is not null)
-            allowedParallelism = be9.RequestCores(allowedParallelism);
+        try
+        {
+            if (be9 is not null)
+                allowedParallelism = be9.RequestCores(allowedParallelism);
+        }
+        catch(NotImplementedException)
+        {
+            // RequestCores is not implemented in TaskHostFactory
+            be9 = null;
+        }
+
         try
         {
             ParallelLoopResult result = Parallel.ForEach(Assemblies,

src/tasks/WasmAppBuilder/EmccCompile.cs

@@ -132,8 +132,16 @@ private bool ExecuteActual()
 
                 int allowedParallelism = DisableParallelCompile ? 1 : Math.Min(SourceFiles.Length, Environment.ProcessorCount);
                 IBuildEngine9? be9 = BuildEngine as IBuildEngine9;
-                if (be9 is not null)
-                    allowedParallelism = be9.RequestCores(allowedParallelism);
+                try
+                {
+                    if (be9 is not null)
+                        allowedParallelism = be9.RequestCores(allowedParallelism);
+                }
+                catch(NotImplementedException)
+                {
+                    // RequestCores is not implemented in TaskHostFactory
+                    be9 = null;
+                }
 
                 /*
                     From: https://github.com/dotnet/runtime/issues/46146#issuecomment-754021690

src/tasks/WasmAppBuilder/ForceMSBuildGC.cs

@@ -0,0 +1,19 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using Microsoft.Build.Framework;
+using Microsoft.Build.Utilities;
+
+namespace Microsoft.WebAssembly.Build.Tasks
+{
+    public class ForceMSBuildGC : Task
+    {
+        public override bool Execute()
+        {
+            GC.Collect();
+            GC.WaitForPendingFinalizers();
+            return true;
+        }
+    }
+}

src/tests/build.proj

@@ -291,7 +291,7 @@
   </Target>
 
   <UsingTask TaskName="AppleAppBuilderTask" AssemblyFile="$(AppleAppBuilderTasksAssemblyPath)" />
-  <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" />
+  <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" TaskFactory="TaskHostFactory" />
 
   <Target Name="BuildMonoiOSApp">
     <PropertyGroup>

src/tools/illink/src/ILLink.Tasks/build/Microsoft.NET.ILLink.targets

@@ -127,7 +127,7 @@ Copyright (c) .NET Foundation. All rights reserved.
     if the output semaphore file is out of date with respect to the inputs.
     ============================================================
     -->
-  <UsingTask TaskName="ILLink" AssemblyFile="$(ILLinkTasksAssembly)" Condition="'$(ILLinkTasksAssembly)' != ''" />
+  <UsingTask TaskName="ILLink" AssemblyFile="$(ILLinkTasksAssembly)" Condition="'$(ILLinkTasksAssembly)' != ''" TaskFactory="TaskHostFactory" />
   <Target Name="_RunILLink"
           DependsOnTargets="_ComputeManagedAssemblyToLink;PrepareForILLink"
           Inputs="$(MSBuildAllProjects);@(ManagedAssemblyToLink);@(TrimmerRootDescriptor);@(ReferencePath)"
@@ -312,7 +312,7 @@ Copyright (c) .NET Foundation. All rights reserved.
     Compute the set of inputs to ILLink.
     ============================================================
     -->
-  <UsingTask TaskName="ComputeManagedAssemblies" AssemblyFile="$(ILLinkTasksAssembly)" Condition="'$(ILLinkTasksAssembly)' != ''" />
+  <UsingTask TaskName="ComputeManagedAssemblies" AssemblyFile="$(ILLinkTasksAssembly)" Condition="'$(ILLinkTasksAssembly)' != ''" TaskFactory="TaskHostFactory" />
   <Target Name="_ComputeManagedAssemblyToLink" DependsOnTargets="_ComputeAssembliesToPostprocessOnPublish">
 
     <!-- NB: There should not be non-managed assemblies in this list, but we still give the ILLink a chance to