The total physical memory of 3GB iOS devices is very tight. After system memory occupation, the available memory for third-party apps is extremely insufficient, leading to frequent OOM termination. Enabling or disabling JavaScriptCore causes a huge difference in app memory crash threshold. Without JSC, the app will crash at only 1.52GB memory usage, which severely restricts normal business running. The common 4MB and 8MB memory allocation used in our project falls into the high memory fragmentation range defined by libmalloc, resulting in the lowest memory crash limit and worst stability. Our core business relies heavily on JSC environment for JS interaction, resource rendering and dynamic logic execution. We cannot shut down JSC, but 3GB devices still face serious memory shortage even with JSC enabled. Mass users with 3GB RAM old iOS devices suffer from frequent app crashes, freeze, background kill and loading failure, which badly damage user experience and product reputation. We have finished all app-level memory optimization: adjust allocation size, optimize memory release, reduce resident memory, but still cannot break through the fixed memory crash limit. There is no effective solution on application layer. We sincerely ask Apple official engineers to provide official suggestions, system-level memory tuning solutions and JSC memory scheduling optimization guidance to solve the memory limit bottleneck on 3GB RAM iOS devices.