Abstract: A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However，modern cache management rarely considers this fine-grained feature，which impacts the effective cache capacity of contemporary high-performance spacecraft processors.To harness these nonuniform access behaviors，an efficient cache replacement framework featuring an auxiliary cache specifically designed to retain evicted hot data was proposed.This framework reconstructs the cache replacement policy，facilitating data migration between the main cache and the auxiliary cache.Unlike traditional cacheline-granularity policies，the approach excels at identifying and evicting infrequently used data，thereby optimizing cache utilization.The evaluation shows impressive performance improvement，especially on workloads with irregular access patterns.Benefiting from fine granularity，the proposal achieves superior storage efficiency compared with commonly used cache management schemes，providing a potential optimization opportunity for modern resource-constrained processors，such as spacecraft processors.Furthermore，the framework complements existing modern cache replacement policies and can be seamlessly integrated with minimal modifications，enhancing their overall efficacy.

Key words: spacecraft processors, cache management, replacement policy, storage efficiency, memory hierarchy, microarchitecture