Profiling support in SDKs

[brancz]

Now that [Profiling in OpenTelemetry has entered the Alpha stage], it is time to start implementating it in SDKs and bring back feedback coming from this implementation phase to the profiling SIG. This issue acts as the umbrella issue to track the progress in various SDKs, please make sure to add issues to this issue that track support for each language.

Language	Profiles support status	Trace/span ID correlation with eBPF profiler	Tracking issue
C++	Not started.	Not implemented. Via thread-context-sharing.
C#/.NET	Not started.	Not implemented. Likely via thread-context-sharing.
Erlang/Elixir	Not started.	Not implemented. Unclear whether it can be achieved via thread-context-sharing, tbd.
Go	Not started.	✅ Native support for goroutine labels already contributed to ebpf profiler by Polar Signals
Java	Development. Planned: JFR-based CPU + allocation profiles via the Java agent. JFR events shim currently in opentelemetry-java-contrib.	Not implemented. Native extension + thread-context-sharing
JavaScript	Not started.	Not implemented. Polar Signals has a battle-tested existing solution.	open-telemetry/opentelemetry-js#6500
Kotlin (Android)	Not started.	Not applicable?
PHP	Not started.	Not implemented. Unclear whether thread-context-sharing helps, tbd.
Python	Not started.	Not implemented. Likely via 3.14's PyContext_AddWatcher combined with thread-context-sharing.
Ruby	Not started.	Not implemented.
Rust	Not started.	Not implemented. Via thread-context-sharing.	open-telemetry/opentelemetry-rust#3460
Swift	Not started.	Not implemented. Via thread-context-sharing.

[ivoanjo]

PR with Rust implementation: open-telemetry/opentelemetry-rust#3460

[ivoanjo]

Maybe useful to split the column between process and thread context? E.g. maybe some languages the trace/span info is not feasible (or at least will need some special assistance e.g. I've no idea how we'll do stuff for Erlang), but we process context would still be possible as a start

[NimrodAvni78]

I've opened an issue in opentelemetry-js to add profiling support so i am adding it here for tracking
also i have attached an example implementation of parts of the profiling SDK plus a profiler for wall clock / memory with Trace/Span ID correlation (only for wall clock profiling)