Observe NOTAM changes instead of polling on the main actor#11
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`setupRunwayNOTAMObservation` ran a 500ms `Task { @mainactor … }` loop for
the lifetime of the takeoff/landing screen, faulting the selected
runway's NOTAM through the main `ModelContext` twice a second to detect
edits. That recurring main-thread SwiftData access contends with the
persistent store coordinator and contributes to the launch-time
`performBlockAndWait` hangs (SF50-TOLD-26/-20), which remain active on
3.5.6.
Replace the poll with `withObservationTracking` — the same Observation
mechanism the NOTAM editing views already use. The main actor now reads
the NOTAM only when it actually changes, never on a timer, and the
observation re-arms itself after each change. A generation token
invalidates the observation registered for a previous runway selection.
Refs SF50-TOLD-26, SF50-TOLD-20.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Reduce the main-actor SwiftData contention behind the launch-time performBlockAndWait hangs (SF50-TOLD-26/-20), and quiet transient Sentry noise: - Stop NavDataLoaderViewModel's perpetual 0.5s state poll once nav data is loaded, so a returning user does zero background SwiftData work after launch (#10). - Observe runway NOTAM changes with withObservationTracking instead of a 500ms main-actor poll for the lifetime of the takeoff/landing screen (#11). - Treat TLS handshake failures (secureConnectionFailed) as transient and stop double-reporting weather-fetch network errors to Sentry (#9). Refs SF50-TOLD-26, SF50-TOLD-20, SF50-TOLD-2D, SF50-TOLD-21. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Summary
Removes a 500ms main-actor SwiftData poll in
BasePerformanceViewModel, part of the launch-time app hangs SF50-TOLD-26 / SF50-TOLD-20 (still active on 3.5.6: 19App Hang Fully Blockedevents on 3.5.6+47).Background
These hangs are the main thread blocked in
-[NSManagedObjectContext performBlockAndWait:].setupRunwayNOTAMObservationran aTask { @MainActor … }loop that, every 500ms for the lifetime of the takeoff/landing screen, faulted the selected runway's NOTAM through the mainModelContextto detect edits. That recurring main-thread fault contends with the persistent store coordinator and stalls the main thread under load.Change
Replace the poll with
withObservationTracking— the same Observation mechanism the NOTAM editing views already rely on:notamObservationToken) invalidates the observation registered for a previous runway selection, so stale chains from rapid runway switches bail out.Behavior is preserved: editing or clearing a NOTAM still re-initializes the model and recalculates.
Testing
swift format lint --strictandswiftlint --strictclean.SF50 TOLDscheme for the iOS 26.5 iPhone 16 simulator — succeeds.The hang reduction itself is a production/contention effect not reproducible on the simulator; this verifies the replacement preserves the recalc-on-NOTAM-change behavior.
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