Enable default features for wasmtime

[rahulchaphalkar]

The default-features=false is not present in wasmtime v9.0.3 c-api ( LINK ) , but it was still present in Cargo.toml in this repo (bazel/cargo/wasmtime/Cargo.toml) This PR removes that i.e. enables default features for wasmtime. This required a cargo raze --generate-lockfile and other associated changes (like removing dups from generated build files). Previous discussion for this is here https://github.com/proxy-wasm/proxy-wasm-cpp-host/issues/313

[rahulchaphalkar]

@PiotrSikora Any issue with enabling this? After enabling default features, a second PR will enable us to support VTune for wasmtime ( a small change in wasmtime.cc in this repo) which in turn will enable wasm code profiling with VTune for Envoy.

[PiotrSikora]

1. At the very least, you need to split this into 2 PRs and separate update of dependencies from enabling default features, otherwise this is unreviewable.
2. What's the justification for enabling default features? It enables 6 features and I don't think all of them should be enabled.

[rahulchaphalkar]

2. What's the justification for enabling default features?

I can just enable one feature, 'vtune' instead of all default features. I just assumed Cargo.toml here is following wasmtime/crates/c-api/Cargo.toml in wasmtime repo, so followed the changes there.

1. split this into 2 PRs

If i understand this correctly, I can have 1st PR where I just update deps with cargo raze --generate-lockfile, fix the dup deps issue. And in 2nd PR, update with feature vtune, fix any additional dep issues that might arise from it after rerunning cargo raze --generate-lockfile.

[PiotrSikora]

I can just enable one feature, 'vtune' instead of all default features.

vtune is not c-api feature, so it wouldn't be enabled with this change anyway, would it?

I just assumed Cargo.toml here is following wasmtime/crates/c-api/Cargo.toml in wasmtime repo, so followed the changes there.

That was the case, but not all default features make sense in context of Proxy-Wasm C++ Host.

If i understand this correctly, I can have 1st PR where I just update deps with cargo raze --generate-lockfile, fix the dup deps issue. And in 2nd PR, update with feature vtune, fix any additional dep issues that might arise from it after rerunning cargo raze --generate-lockfile.

Correct. Ideally, you could update Wasmtime to the latest version in the process.

[rahulchaphalkar]

vtune is not c-api feature

Right, I was planning on enabling it for the wasmtime dependency in c-api, similar to how cranelift is enabled (i would add back default features = false - https://github.com/proxy-wasm/proxy-wasm-cpp-host/blob/2459f9ba5dfb9f7efdee50b1911611dc9bb09973/bazel/cargo/wasmtime/Cargo.toml#L14

Ideally, you could update Wasmtime

Sure, I can update wasmtime to its latest v13.0.0 and update deps in 1st PR, and then enable vtune in 2nd PR (and some associated bazel config options).

On the default features - I had hoped that features like pooling-allocator and parallel-compilation would be helpful for perf in some cases. Would it make sense to enable these on a case-by-case basis down the road (after some initial investigation/perf estimates in a separate issue)?

[PiotrSikora]

On the default features - I had hoped that features like pooling-allocator and parallel-compilation would be helpful for perf in some cases. Would it make sense to enable these on a case-by-case basis down the road (after some initial investigation/perf estimates in a separate issue)?

Enabling features one-by-one is fine, if justified.

[rahulchaphalkar]

PR (1/2) opened for updating wasmtime, https://github.com/proxy-wasm/proxy-wasm-cpp-host/pull/368