Utility-Based Cache Partitioning: Making Shared Caches Smarter in Multi-Core Systems

In modern computing systems, performance is no longer determined by a single powerful core. Instead, today’s processors rely on multiple cores working together to execute programs efficiently. While this design significantly improves overall throughput, it also introduces new challenges — especially when hardware resources are shared among cores. One such shared resource is the Last-Level Cache (LLC). The LLC plays a critical role in reducing memory access latency and improving processor performance. However, when multiple cores share the same cache, competition arises. This competition can lead to cache contention, unfair resource distribution, and performance degradation. This is where Utility-Based Cache Partitioning (UCP) becomes important. The Problem with Shared Caches In multi-core processors designed by companies like Intel and AMD, the last-level cache is shared across all cores. While sharing improves average efficiency, it does not guarantee fairness. Imagine two application