Instruments, responsiveness, energy, launch, and networking
Measurement starts after a budget fails. Field Notes uses a repeatable 2,000-note scroll fixture so a hitch regression can be reproduced before code changes.
Design the boundary
- Capture the matching release build, fixture, device, OS, thermal state, network profile, run count, and variance.
- Use Time Profiler for CPU, Allocations and Leaks for memory, hang and hitch tools for responsiveness, and network instruments for transfers.
- Fix the dominant measured cost, rerun the same matrix, and retain before and after traces.
- Simulator traces help diagnose code paths but do not establish physical-device energy or launch budgets.
Validation boundary
No Instruments or physical-device trace was captured for this content batch.
Series navigation
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