VSTHRD002 and VSTHRD010 - Performance issues?

[jirikanda]

I would like to share my observation regarding build performance when using the VSTHRD002UseJtfRunAnalyzer and VSTHRD010MainThreadUsageAnalyzer.

Observation

We observe that the build takes significantly longer than expected in a project that uses:

• Microsoft.VisualStudio.Threading.Analyzers
• .NET 10
• EF Core 10 with Code Migrations.

Build duration comparison (with analyzers vs. no analyzers):

dotnet build → ~58 seconds.
dotnet build -p:RunAnalyzers=false → ~10 seconds.

Analyzer timing from MSBuild.exe /v:d /p:reportanalyzer=true shows

Time (s)    %   Analyzer
  668,239   99   Microsoft.VisualStudio.Threading.Analyzers.CSharp, Version=17.14.15.42505, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
  370,871   55      Microsoft.VisualStudio.Threading.Analyzers.VSTHRD010MainThreadUsageAnalyzer (VSTHRD010)
  290,486   43      Microsoft.VisualStudio.Threading.Analyzers.VSTHRD002UseJtfRunAnalyzer (VSTHRD002)
  3,736   <1      Microsoft.VisualStudio.Threading.Analyzers.VSTHRD103UseAsyncOptionAnalyzer (VSTHRD103)
  1,340   <1      Microsoft.VisualStudio.Threading.Analyzers.CSharpVSTHRD110ObserveResultOfAsyncCallsAnalyzer (VSTHRD110)
  1,252   <1      Microsoft.VisualStudio.Threading.Analyzers.CSharpVSTHRD012SpecifyJtfWhereAllowed (VSTHRD012)
  0,196   <1      Microsoft.VisualStudio.Threading.Analyzers.CSharpVSTHRD109AvoidAssertInAsyncMethodsAnalyzer (VSTHRD109)

The two analyzers (VSTHRD010 and VSTHRD002) account for the large majority of analyzer execution time.

Project details

• The EF Core model contains ~100 model entities (SQL Server tables) in a Model project.
• An Entity contains DbContext and 175 database migrations.
• Each migration consist of two files:
  • the migration itself
  • and the "*.Designer.cs" file.
• The designer files in project grow in time from ~60 kB to ~180 kB.
• Total size of designer files in Entity project is 22,16 MB.
• Total size of code files in Entity project is 22,86 MB.

[AArnott]

Thanks for your analysis and feedback.
I'd have to check on VSTHRD002 to see if there's something we can improve there, but VSTHRD010 has been looked at before, and I'm afraid there's not much we can do to speed things up. If you're in a project that has no 'main thread' requirements, I suggest you turn off that particular analyzer which will avoid the perf hit.

[drewnoakes]

... "*.Designer.cs" files ...

@jirikanda if you exclude these analyzers from the designer files via .editorconfig, does perf improve?

[jirikanda]

Thank you guys, I appreciate your tips to improve the perf.

@drewnoakes
I have added this section to the .editorconfig. I haven't found a better way to target *.Designer.cs files then using */Migrations/*.cs. Even though it catches more files, it works well also for *.Designer.cs files.
(Neither *.Designer.cs nor **.Designer.cs works here.)

[*/Migrations/*.cs]
generated_code=true

dotnet_diagnostic.VSTHRD002.severity = none
dotnet_diagnostic.VSTHRD010.severity = none

I was surprised it partially helped, it kicked out the VSTHRD002UseJtfRunAnalyzer, but VSTHRD010MainThreadUsageAnalyzer still remains.
It improved the build time about 40%. Not great, not terrible, every second counts.

Time (s)    %   Analyzer
   386,228   99   Microsoft.VisualStudio.Threading.Analyzers.CSharp, Version=17.14.15.42505, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
  382,222   98      Microsoft.VisualStudio.Threading.Analyzers.VSTHRD010MainThreadUsageAnalyzer (VSTHRD010)
  1,893   <1      Microsoft.VisualStudio.Threading.Analyzers.VSTHRD103UseAsyncOptionAnalyzer (VSTHRD103)
  1,037   <1      Microsoft.VisualStudio.Threading.Analyzers.CSharpVSTHRD110ObserveResultOfAsyncCallsAnalyzer (VSTHRD110)
  0,702   <1      Microsoft.VisualStudio.Threading.Analyzers.CSharpVSTHRD012SpecifyJtfWhereAllowed (VSTHRD012)

(I have updated the original issue to correct the name of the analyzer, it is an analyzer, not a codefix.)

[AArnott]

Neither *.Designer.cs nor **.Designer.cs works here.

What about [**/*.Designer.cs]?

[jirikanda]

@AArnott, thanx for tip, it works. I mean, with this pattern, it works same as mention in my previous post - build time reduced by 40%.

[akonyer]

I have the exact same issue! Microsoft.VisualStudio.Threading.Analyzers is making my build time 2-3x slower!

[drewnoakes]

@akonyer do the workarounds given here help?

[noelex]

I have the same issue. I tried setting severity of VSTHRD010 to none in .editorconfig, but it still shows up in Analyzer Report:

[AArnott]

@noelex @ad-eg-dk see #1563 for how to disable the analyzer altogether.