_GetProjectReferenceTargetFrameworkProperties is extremely slow for F# projects

[saul]

The _GetProjectReferenceTargetFrameworkProperties target appears to take a significant amount of time to complete. This is in relation to F# projects, I can't seem to reproduce the issue with C# projects. I've exacerbated the issue by creating a solution of 100 projects, where by each project has a reference to all of the previous projects (e.g. Project4 references Project1, Project2 and Project3) as a minimal reproduction.

MSBuild: Target Performance Summary:
MSBuild:         0 ms  BeforeCompile                              1 calls
MSBuild:         0 ms  SetWin32ManifestProperties                 1 calls
MSBuild:         0 ms  BeforeResolveReferences                    1 calls
MSBuild:         0 ms  AfterResolveReferences                     1 calls
MSBuild:         0 ms  _AfterCompileWinFXInternal                 1 calls
MSBuild:         0 ms  _ComputeNonExistentFileProperty            1 calls
MSBuild:         0 ms  AfterCompile                               1 calls
MSBuild:         0 ms  PrepareProjectReferences                   1 calls
MSBuild:         0 ms  GetFrameworkPaths                          1 calls
MSBuild:         0 ms  ResolveReferences                          1 calls
MSBuild:         0 ms  AfterCompileWinFX                          1 calls
MSBuild:         1 ms  GetReferenceAssemblyPaths                  1 calls
MSBuild:         1 ms  DesignTimeXamlMarkupCompilation            1 calls
MSBuild:         1 ms  ResolveSDKReferences                       1 calls
MSBuild:         1 ms  _SetEmbeddedWin32ManifestProperties        1 calls
MSBuild:         1 ms  ExpandSDKReferences                        1 calls
MSBuild:         1 ms  Compile                                    1 calls
MSBuild:         2 ms  DesignTimeMarkupCompilation                1 calls
MSBuild:         2 ms  PrepareForBuild                            1 calls
MSBuild:         2 ms  GenerateTargetFrameworkMonikerAttribute    1 calls
MSBuild:         2 ms  ImplicitlyExpandDesignTimeFacades          1 calls
MSBuild:         2 ms  ResolveAssemblyReferences                  1 calls
MSBuild:         2 ms  GetTargetFrameworkProperties              68 calls
MSBuild:         4 ms  _GenerateCompileInputs                     1 calls
MSBuild:         4 ms  GetTargetPath                             68 calls
MSBuild:         4 ms  _SplitProjectReferencesByFileExistence     1 calls
MSBuild:         4 ms  AssignProjectConfiguration                 1 calls
MSBuild:         5 ms  _GenerateCompileDependencyCache            1 calls
MSBuild:         7 ms  CoreCompile                                1 calls
MSBuild:        23 ms  GetInstalledSDKLocations                   1 calls
MSBuild:     49632 ms  ResolveProjectReferences                   1 calls
MSBuild:     107337 ms  _GetProjectReferenceTargetFrameworkProperties  68 calls
MSBuild: 
MSBuild: Task Performance Summary:
MSBuild:         0 ms  GetReferenceAssemblyPaths                  1 calls
MSBuild:         0 ms  Hash                                       1 calls
MSBuild:         0 ms  GetFrameworkPath                           1 calls
MSBuild:         0 ms  MakeDir                                    1 calls
MSBuild:         0 ms  FindAppConfigFile                          1 calls
MSBuild:         0 ms  CallTarget                                 1 calls
MSBuild:         0 ms  ResolveAssemblyReference                   1 calls
MSBuild:         1 ms  Fsc                                        1 calls
MSBuild:         2 ms  WriteLinesToFile                           1 calls
MSBuild:         4 ms  ResolveNonMSBuildProjectOutput             1 calls
MSBuild:         4 ms  AssignProjectConfiguration                 1 calls
MSBuild:     156729 ms  MSBuild                                   69 calls

The fact that this happens with F# and not C# leads me to believe there's something in the C# common targets that is missing from the F# common targets that improves the performance of this target.

It is also worth noting that the _ResolveReferenceDependencies property is set to true, although setting it to false has minimal effect.

See dotnet/fsharp#2107 for more details.

[saul]

This issue looks like it's in the same area as #1276, cc @rainersigwald

[rainersigwald]

I do suspect this is a duplicate of #1276, but as I mentioned there (#1276 (comment)), I think it's mostly that this target gets blamed for initial blocked-waiting time, rather than is truly slow. If you see evidence to the contrary on F# projects specifically please let us know and we can reopen this issue.