[Performance]: MSBuild.exe spends 300 ms JITting Microsoft.DotNet.MSBuildSdkResolver.dll

[ladipro]

Issue Description

We currently load SDK resolvers using Assembly.LoadFrom on .NET Framework, which disqualifies it from using native images even if they existed. We should:

• Figure out a way to use regular Assembly.Load, e.g. load into a separate appdomain with a generated app config.
• Make sure the .NET SDK resolver and the NuGet SDK resolver assemblies are added to the NGEN queue by Visual Studio installer and produce usable images.

The potential perf gain is about 300 ms of JITting saved, out of 1100 ms total for a simple app build using MSBuild.exe. It should also lay some groundwork for eliminating another big chunk of JITting: Microsoft.NET.Build.Tasks.dll.

Steps to Reproduce

Collect JIT stats of:

> MSBuild.exe SimpleProject.csproj

Data

Analysis

No response

Versions & Configurations

No response

Regression

• yes
• no

Regression Details

No response

[rainersigwald]

• Make sure the .NET SDK resolver and the NuGet SDK resolver assemblies are added to the NGEN queue by Visual Studio installer and produce usable images.

This one will surely be Interesting™️. We should talk to @joeloff.

[ladipro]

My understanding is that the resolvers are shipped with VS, located under MSBuild\Current\Bin\SdkResolvers so they have to already be playing well with the VS installer. Binaries shipped in the SDK (e.g. Microsoft.NET.Build.Tasks.dll) are a different story, indeed.