Skip Invariant initialization test for CultureData.Invariant

[benaadams]

It currently goes through an expensive test PopulateIsAsciiCasingSameAsInvariant to check if Invariant is equivalent to Invariant which can be skipped; which shows up in startup (when running ToUpperInvariant for the first time to get the Guid to initialize an ASP.NET EventSource)

Before

After

/cc @GrabYourPitchforks

Contributes to #44598

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Issue Details

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It currently goes through an expensive test to check if Invariant is equivalent to Invariant which can be skipped; which shows up in startup (when running ToUpperInvariant for the first time to get the Guid to initialize an ASP.NET EventSource)

Before

After

/cc @GrabYourPitchforks

Author:	benaadams
Assignees:	-
Labels:	area-System.Globalization
Milestone:	-

[ShreyasJejurkar]

Hey @benaadams, are these profiling tools are of VS? Or you are using something else? Just a side question. 😊

[benaadams]

@MCCshreyas dotTrace Timeline viewer; https://www.jetbrains.com/help/profiler/Timeline_Viewer_Concepts.html is good when you want to zoom in to what happened when

[ShreyasJejurkar]

Ohhh very thanks @benaadams for reply. I will get that! Need to find some resources on how to use it effectively! Any suggestions!?

[benaadams]

@MCCshreyas You can do a similar thing with the VS profiler; however the docs for dotTrace in timeline view are here (with gifs, that play if you click them) https://www.jetbrains.com/help/profiler/Get_Started_with_Timeline_Profiling_(Basic).html#subsystems

For looking at the runtime specifically and getting a breakdown for the native methods (including Jit, GC, VM); and then seeing the effect of any changes you'll have to build the runtime (this repo)

.\build -c Release

Then copy the files from
runtime\artifacts\bin\coreclr\windows.x64.Release and the pdb files from runtime\artifacts\bin\coreclr\windows.x64.Release\PDB to an app that you have published selfcontained:

  <PropertyGroup>
    <TargetFramework>net5.0</TargetFramework>
    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
    <PublishReadyToRun>True</PublishReadyToRun>
    <SelfContained>true</SelfContained>
  </PropertyGroup>

dotnet publish -c Release

Note: before each recompile of the runtime you'll have to delete System.Private.CoreLib.ni.pdb from the pdb directory otherwise it will keep appending to the end and not pickup the changes properly #35489

For dotTrace specifically; only the timeline view will give you a breakdown of the native methods (when you include the native runtime pdbs in the apps publish directory); the other modes will only look at the managed code

[ShreyasJejurkar]

ohh @benaadams, really thankful for this information. Am currently looking at how I can see method allocations and stuff like that with VS.

I always see yours, @stephentoub, and other people's recent PR on reducing allocations specifically, and you guys are doing a great job. So I always wonder, how you guys are doing this much analysis, so I asked you. I am quite new to this kind of C# and related stuff (like micro-optimization and allocations), seems like it's a lot to learn yet for me.

Really thank you @benaadams, really appreciated it. 🥇

[benaadams]

Am currently looking at how I can see method allocations and stuff like that with VS.

Debug -> Performance Profiler -> .NET Object Allocation Tracking

You can also open a dmp file directly in VS that will give you a static view of what is allocated; and can use the dotnet-dump tool to create them https://docs.microsoft.com/en-us/dotnet/core/diagnostics/dotnet-dump

[ShreyasJejurkar]

Oh ok, I think I need to install profiling workload to get this in VS, as by default I only have CPU and Memory profiler. I will get this and will explore for sure! Thanks again! 😊