[wasm-ep] Tracking

[lambdageek]

Basics:

• [wasm-ep] Minimal diagnostic tracing configuration and sample #69158
  This adds support for using the JS console to create an EventPipe session with the default providers and to collect a trace in-memory to the Emscripten VFS and to egress it to a JavaScript Blob object (which can then be downloaded).
• [wasm-ep] Implement EventSource counters support; add an EventPipeSessionOptions builder to TS #69567
  • Add support for specifying the providers for a session.
  • Allow the EventSource counter polling thread to start.

Build and SDKs

• Save runtime artifacts from the EventPIpe build in an ep subfolder in the runtime pack (in addition to mt and plain) (variant of [wasm-mt] place multi-threaded wasm build into separate artifacts folders #68506) we ended up with separate runtime packs selected using MonoWasmBuildVariant=perftrace or MonoWasmBuildVariant=multithread in Add support for building WASM variants alongside single-threaded to the build system #71054
• SDK property to build the app with profiling enabled using the ep variant of the runtime artifacts The browser-wasm SDK should automatically reference the threading/perf-tracing ref assemblies #72872

Profiled AOT

The goal is to make it possible to add "something" to a webassembly project in order to cause it to collect a nettrace file that can be fed to the dotnet-pgo tool to produce an .mibc file which can be consumed by the Mono AOT compiler.

• [mono][eventpipe] Implementing MethodDetails and BulkType events #68571
• [wasm-ep] Add a hook to start an EventPipe Session from runtime startup #69674
• [wasm-ep] Implement DiagnosticServer and startup sessions for WebAssembly #72482
• [wasm-ep] End-to-end workflow for profiled AOT using EventPIpe #72481

Sample profiling

The goal is to make it possible to collect a meaningful profile of the main browser thread while it is running managed code

• Figure out why no samples are collected for a mostly async app.
• Identify a good default sampling frequency

Mixed C#/JS perf Integration

• Add a way for JavaScript to push events to EventSources.
  • Maybe add ability to define EventSources in JS?
• Integrate/interop and collect from the JS Performance Timeline API
• Converse integration: export EventPipe events into the browser's perf timeline

Streaming EventPipe sessions

The goal is to make it possible to create a WebSocket connection back to the dev server to send live streaming EventPipe session data to the user.

• Document the WebSocket diagnostic server workflow [docs] begin documenting how to use EventPipe-based profiled AOT for Mono #72864
• Diagnostic server support [wasm-ep] Implement DiagnosticServer and startup sessions for WebAssembly #72482
  The goal is to make it possible to start and stop EventPipe sessions using a dotnet-dsrouter and dotnet-counters/dotnet-trace/etc combo when running a dev server.
• [dsrouter] Implement a WebSocket server diagnostics#3422 (prototype dotnet-dsrouter server-websocket is https://github.com/lambdageek/diagnostics/tree/wasm-server)
• [wasm-ep] Configure the Diagnostic Server using DOTNET_DiagnosticPorts #73011
• Integrate the diagnostic server into the AspNet dev server
• build tooling integration
• VS integration
• Refactor runtime startup to allow the diagnostic server to async pause the browser thread.
  Break up runtime startup such that it can return to the JS event loop after enough initialization is done so that EventPipe sessions can be created (but not yet streaming). Then the diagnostic server can receive commands to create sessions, and the runtime is paused but the browser UI is responsive. (Maybe we can pop up a modal view with the dotnet-dsrouter command and disable UI interactions)

Issues

• [wasm-ep] Can't have both runtime and EventSource event providers in the same session #69568

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Issue Details

---

Basics:

• [wasm-ep] Minimal diagnostic tracing configuration and sample #69158
  This adds support for using the JS console to create an EventPipe session with the default providers and to collect a trace in-memory to the Emscripten VFS and to egress it to a JavaScript Blob object (which can then be downloaded).
• Add support for specifying the providers for a session

Profiled AOT

The goal is to make it possible to add "something" to a webassembly project in order to cause it to collect a stack trace

• [mono][eventpipe] Implementing MethodDetails and BulkType events #68571
• Add a hook to start an EventPipe Session from runtime startup

Sample profiling

The goal is to make it possible to collect a meaningful profile of the main browser thread while it is running managed code

• Figure out why no samples are collected for a mostly async app.
• Identify a good default sampling frequency

Streaming EventPipe sessions

The goal is to make it possible to create a WebSocket connection back to the dev server to send live streaming EventPipe session data to the user.

Diagnostic server support

The goal is to make it possible to start and stop EventPipe sessions using a dotnet-dsrouter and dotnet-counters/dotnet-trace/etc combo when running a dev server.

Author:	lambdageek
Assignees:	-
Labels:	arch-wasm, untriaged, area-Tracing-mono
Milestone:	-