⏱️ Add cross-platform ability to profile guest code in run mode #280
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itsrainy
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itsrainy
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lib/src/execute.rs
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| eprintln!(); | ||
| eprintln!("Profile written to: {}", path.display()); | ||
| eprintln!("View this profile at https://profiler.firefox.com/."); |
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Newbie question: why are we writing what looks to be a success message to stderr?
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oops I don't think that was intentional
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I had done it that way in the equivalent code in Wasmtime to reduce the chance that this message might get mixed up with regular output from the wasm guest. I don't feel strongly about whether Viceroy should do the same, where guest output is less likely to be significant.
| self, | ||
| program_name: &str, | ||
| args: &[String], | ||
| guest_profile_path: Option<&PathBuf>, |
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Question: Does this change, introducing a new parameter to a public function, mean we will need to release this as a new major version of the crate?
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I'm presuming "no" because it's an additive change to the exposed binary interface (i.e. a new optional flag has been added) but if the user doesn't provide that flag the existing functionality continues to work as expected.
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Sorry, I meant for the viceroy-lib crate, not for the cli crate
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Yes I think this will probably require a bump to 0.6.0
JakeChampion
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upgraded to wasmtime 10.0.0
Co-authored-by: Jamey Sharp <jsharp@fastly.com>
Co-authored-by: Jamey Sharp <jsharp@fastly.com>
JakeChampion
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This uses the GuestProfiler that is now available in wasmtime 10.0.0 to create a profile in a location specified by the user. Right now we currently just have it working for run-mode, but are planning on adding similar functionality in serve mode, likely creating one profile per-request.
To use this, run the following:
This will result in a profile being saved to the default location (
guest-profile.json), which you can upload and view on https://profiler.firefox.com.