+poc,instruments PoC of an Instruments.app instrument "tracing" (naive) #97
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| @@ -36,7 +36,7 @@ public protocol Span { | |||
| var endTimestamp: Timestamp? { get } | |||
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| /// The read-only `BaggageContext` of this `Span`, set when starting this `Span`. | |||
| var baggage: BaggageContext { get } | |||
| var context: BaggageContext { get } | |||
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IMHO these should be context because span.context rather than span.baggage.
The baggage word is only to be used to disambiguate in cases like context.context so this isn't one of those cases IMO. (rules we arrived at https://github.com/slashmo/gsoc-swift-baggage-context#existing-context-argument )
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requires major version bump ;-)
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The project was never tagged so we're not even a 0.0.0, a major bump from nothing still is nothing 😉
| // ==== ---------------------------------------------------------------------------------------------------------------- | ||
| // MARK: OSSignpost Tracing | ||
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| @available(OSX 10.14, *) |
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since signposts are only available since then.
(I may have gotten the availability wrong on other OSes)
| import Instrumentation | ||
| import Foundation // string conversion for os_log seems to live here | ||
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| #if os(macOS) || os(tvOS) || os(iOS) || os(watchOS) |
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this is an apple platforms only thing
| @available(watchOS 3.0, *) | ||
| enum OSSignpostTracingKeys { | ||
| enum TraceParentIDs: BaggageContextKey { | ||
| typealias Value = [OSSignpostID] |
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not "really" used and I don't think there's a good way to make use of this info in instruments... though I may have to learn more about it. Not a huge goal of this PoC anyway.
| <name>Konrad `ktoso` Malawski</name> | ||
| </owner> | ||
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| <!-- Instruments Developer Help: https://help.apple.com/instruments/developer/mac/current/ --> |
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see here for docs how this format works, and also WWDC sessions on custom instruments:
| </os-signpost-interval-schema> | ||
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| <!-- MARK: Instrument Definitions --> | ||
| <instrument> |
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just a simple instrument that shows each span (grouped by operation name) as it's own row.
This is obviously would not scale all that well in reality, but it's good for the PoC.
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Can this be merged, it's just another showcase -- wdyt @slashmo ? I'll rebase after review. |
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I think this would be very useful with NIO channels, to see in Xcode when exactly - including the order- each job is run. |
| public func startSpan( | ||
| named operationName: String, | ||
| context: BaggageContext, | ||
| ofKind kind: SpanKind, | ||
| at timestamp: Timestamp? | ||
| ) -> Span { | ||
| OSSignpostSpan( | ||
| log: self.log, | ||
| named: operationName, | ||
| signpostName: self.signpostName, | ||
| context: context | ||
| // , kind ignored | ||
| // , timestamp ignored, we capture it automatically | ||
| ) | ||
| } | ||
| } |
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note that some tracer may choose not to expose setting the timestamp explicitly by user.
this is the case with XRay tracer as well, at the moment (I dont really see a use case for that);
arguably its easier to change XRay tracer than OSSignpostSpan ;-)
BTW this is not required by OT
...tsAppTracingInstrpkg/SpansExampleInstrument/SpansExampleInstrument.xcodeproj/project.pbxproj
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@ktoso Yep, sorry for the delay |
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Thanks folks, just another fun example to include in the suite, merged then |
Since I had a moment over the holidays here I picked up a PoC i wanted to sanity check since a while.
Context: Since a few years Instruments allows for building custom instruments (yeah all the words are terribly overloaded here but I don't think we can do much about that to be honest). See session: https://developer.apple.com/wwdc18/410 Creating Custom Instruments - WWDC 2018
PoC / "Use Case" of using the tracing instruments API with signposts and collecting in instruments.
This is by no means super end to end perfect, but showcases somewhat the shape and how compatible (or not) the APIs are.
It's fairly okey, the fact that spans are classes means we can easily use them in signpost IDs which is good.
Some comments inline.
❗ THIS IS JUST A POC, NOT END GOAL OR "VERY REAL" TRACER ❗
Result: