simslim-mirror/docs/category-memory.md

Category memory estimates

The GUI's category values estimate the extra idle phys_footprint retained when a category is kept enabled. They are guidance for choosing a profile, not memory budgets or guarantees.

Method

• Runtime: iOS 26.5
• Device: one otherwise idle simulator with no test app workload
• Baseline: a fully slim clean boot, median of five samples after a 20-second settle
• Category run: a clean boot with only that category kept enabled, median of three samples after a 15-second settle
• Measurement: simslim measure, which sums process phys_footprint

The final fully slim baseline was 1,113.4 MiB. Category estimates are each category run's median minus that baseline, rounded to a useful GUI value.

Category	Measured delta	GUI estimate
Widgets & Wallpaper	674.7 MiB	675 MB
Siri & Intelligence	266.7 MiB	265 MB
Spotlight & Search	50.2 MiB	50 MB
iCloud & Apple Account	98.6 MiB	100 MB
App Store, Push & Media	80.1 MiB	80 MB
Mail, Calendar & Contacts	78.1 MiB	80 MB
Safari Sync & Web Services	49.9 MiB	50 MB
Family & Screen Time	63.0 MiB	65 MB
Health, Home & Fitness	132.7 MiB	135 MB
Photos & Media Analysis	57.9 MiB	60 MB
News, Weather, Maps & Games	88.1 MiB	90 MB
Messaging & FaceTime	60.2 MiB	60 MB
Sharing & Device Connectivity	64.4 MiB	65 MB
Ads, Diagnostics & Telemetry	106.0 MiB	105 MB
Other Background Services	194.0 MiB	195 MB

These deltas are not additive. Services share caches and dependencies, and their footprint changes with simulator runtime, boot age, installed apps, and active workload.

The connectivity category was remeasured after sharingd became always-on to preserve system share sheets. Three alternating clean-boot pairs compared the remaining 11 daemons after the same 20-second settle. Their median deltas were 64.4, 46.4, and 73.4 MiB; the median pair gives the 65 MB GUI estimate. Seven of those daemons stayed resident at idle and directly totaled about 76.2 MiB. The whole-simulator delta is used above for consistency with the other categories.