Memory issue seems fixed in iOS 15.5 for me, NSAllocateMemoryPages failed disappears, memory usage < 600M, but syncing with large data broken on some device. 200MB Sqlite + 70GB assets M1 Max macOS Catalyst(sync success) ==> 3-5 hours(most time for download) + low cpu usage iPad Pro 12.9 5th 16g RAM(sync success) ==> 20 hours active + 5 crashes + half time 100% CPU iPhone Xs  Max(sync failed) ==> 40+ hours syncing with 15gb downloaded + 10 crashes and sync errors + half time 100% CPU

It's not solved yet. iOS 15.3 beta.

Sorry for the late. Sample is uploaded. FB9659774. I known little about instrument, if anything is missing, please tell me. iOS 15.2 beta

it is not fixed on iPadOS/iOS 15.1 beta. 🥲🥲 A TSI is requested.

Update: iOS 15 RC still has this problem. With same data, simulator works fine, while device failed. Memory issue caused by long string or something else?