LRFU Cache Eviction vs Background App Refresh: Balancing Fresh Content with Battery Conservation

Goal: determine how Safari’s LRFU cache eviction interacts with Background App Refresh to balance content freshness against battery consumption on iOS devices.

Constraint: eviction behavior can vary by device model and iOS version, and the “Clear History and Website Data” setting may not fully purge the memory‑resident cache, creating uncertainty about complete invalidation.

Questions: How does disabling Background App Refresh affect the likelihood of serving stale cached resources in Safari? Does the “Clear History and Website Data” setting guarantee immediate removal of the memory‑resident cache, or does it require a full device restart? What measurable impact does extended cache retention have on battery drain during prolonged offline usage?