High CPU when target framework is empty

[davkean]

Opening the following projects causes VS to constantly consume CPU:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework></TargetFramework>
  </PropertyGroup>

</Project>

or

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFrameworks></TargetFrameworks>
  </PropertyGroup>

</Project>

Design time builds are constantly occurring in the background.

Also hit by #3489 by AWS SDK.

[davkean]

Pretty sure this is dependency node.

This was hit by an MVP.

[Pilchie]

@davkean did you look at all? Is this an infinite restore loop?

[jmarolf]

just tried this scenario. Its infinite restore.

[davkean]

It didn't look like infinite restore - it was infinite design-time builds but that will likely be dependency node reinitializing over and over.

[Pilchie]

Oh, right - dupe of #3489 then?

[davkean]

Yep, dup'd it against this one.

[eerhardt]

I'm hitting this in dotnet/corefx after updating the .csproj's to SDK-style projects.

To repro:

1. pull https://github.com/wtgodbe/corefx/tree/SdkProj (the branch from PR Convert all projects to SDK-style corefx#29831).
2. Build once from the root of the repo on the commandline: build.cmd
3. Open src\System.Collections\System.Collections.sln.

However, in my scenario I don't see any design-time builds continually happening using the Build Logging window. However, it is consuming a lot of CPU:

[Pilchie]

Can you collect an ETL trace during this period? https://github.com/dotnet/roslyn/wiki/Recording-performance-traces-with-PerfView