swiftui-performance-audit

To diagnose slow SwiftUI rendering and janky scrolling, audit your code for common bottlenecks like invalidation storms and layout thrash, then validate hypotheses by capturing SwiftUI timeline and Time Profiler data in Instruments to pinpoint exact causes.

Excessive view body updates and high CPU usage in SwiftUI are usually caused by broad state invalidation fan-out, unstable list identity causing identity churn, or heavy main-thread work executing inside view bodies, which Instruments profiling can confirm.

To profile SwiftUI hangs and hitches using Instruments, capture the SwiftUI timeline alongside Time Profiler data to measure long view body updates, identify main-thread bottlenecks, and trace excessive view updates back to their state invalidation source.

Yes, this SwiftUI performance audit applies to profiling across both simulator and physical device for Debug or Release builds, allowing you to capture and compare rendering metrics, CPU usage, and memory growth under different compilation environments.

The best way to fix layout thrash and invalidation storms in SwiftUI is to narrow state and observation fan-out, stabilize list identity, and move heavy computations out of the view body, then validate the remediation with before and after Instruments metrics.

You should profile main-thread work to speed up SwiftUI renders when code review cannot explain slow rendering, janky scrolling, or hangs, and you need evidence-driven Time Profiler data to locate heavy computations or image costs blocking the main thread.