.NET Alloc profiler activation on .NET (Core) about perfview

[brianrob]

I don't believe that the registry is supported for configuring the profiler API for .NET Core. @davmason can you please confirm.

At the same time, you should be able to capture the unsampled allocation events directly in PerfView without using the profiler API at all. This is done by specifying /ClrEvents:Default+GCAllObjectAllocation.

[ocoanet]

I did a few experiments with GCAllObjectAllocation and it seems to generate unsampled Microsoft-Windows-DotNETRuntime/GC/SampledObjectAllocation events. So, indeed, it is a good option to capture allocations for .NET (Core) programs.

But my main issue is that many collection UI options are linked to the CLR profiler. This fact is not clearly documented and these options have no effect on .NET (Core) programs unless the profiler is manually enabled.

I think that both the collection UI and the documentation (PerfView Help) should be improved to make more explicit the behaviors. Also, it would be nice to have an option to enable GCAllObjectAllocation.

I clearly lake experience on the subject to describe a complete solution. I can only make a few suggestions:

1. Either move all CLR-profiler-related options to a specific section, or add a "Profiler" prefix to the options labels.
2. Add a CLR profiler documentation entry to explain its role, usage and activation.
3. Add an option to automatically enable the profiler in the "Run" collection.
4. Rename "ETW .NET Alloc" to "CLR SampAlloc".
5. Add an option "CLR Alloc" (related to GCAllObjectAllocation).

I can probably help on these tasks if needed.