Expose active traces through telemetry server #87
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Tracks currently-active spans in a low-overhead manner (relative to the general overhead of tracing, at least). This is particularly useful because even unsampled traces are available to be viewed here. The model for this functionality is https://pkg.go.dev/golang.org/x/net/trace although there is no built-in viewer here, we expect you to use Chrome's about:tracing or anything that supports the same JSON log format.
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| is_sampled, | ||
| } | ||
| } | ||
| } | ||
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| impl SharedSpan { | ||
| pub(crate) fn into_span(self) -> Arc<parking_lot::RwLock<Span>> { | ||
| Arc::clone(&self.inner) |
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- Since you consume
self, you shouldn't need to clone - Doesn't this return an
Arc<LiveReferenceHandle<...>>iftelemetry-serveris enabled?
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I attempted to reconcile this magical behaviour by defining a newtype struct in a new commit.
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Thanks, that definitely helps make clear what happens here.
| escape(name), | ||
| escape(category), | ||
| match event_type { | ||
| TraceEventType::Begin => "B", |
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async events (those with id) apparently use lowercase "b" and "e" for ph: https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/edit?tab=t.0#heading=h.jh64i9l3vwa1
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Despite the name, async events don't have the right semantics for what we want to express here. Regular events are enough for the visualisation.
| timestamp_us: u64, | ||
| ) { | ||
| self.out.push_str(&format!( | ||
| "{{\"pid\":1,\"name\":\"{}\",\"cat\":\"{}\",\"ph\":\"{}\",\"ts\":{},\"id\":\"{}\"}},", |
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It would be nice to also emit the trace tags as args, but I understand if you don't have time to implement this right now.
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Tags are typed, so we'd need to generate JSON objects with serde or something rather than this quick and dirty approach.
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Yeah, let's leave that for a future iteration
Using a different named type for SharedSpanInner depending on features causes unclear behaviour due to auto-deref. Instead, define a newtype with common methods in both feature variants.
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Nice! |
Required for InspectableSpan trait.
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Tracks currently-active spans in a low-overhead manner (relative to the general overhead of tracing, at least). This is particularly useful because even unsampled traces are available to be viewed here.
The model for this functionality is https://pkg.go.dev/golang.org/x/net/trace although there is no built-in viewer here, we expect you to use Chrome's about:tracing or anything that supports the same JSON log format.
This requires more functionality in our rustracing fork so we can get data set on the spans: cloudflare/rustracing#4