cacheoften

Cacheoften is a caching strategy designed to prioritize frequently accessed items in order to improve hit rates and overall performance. It targets workloads with skewed access patterns by focusing eviction decisions on item popularity alongside recency.

In a typical cache using cacheoften, each cached item maintains an access counter that increments on every hit. Items that accumulate higher popularity are flagged as hot and retained longer, while less frequently accessed items are more likely to be evicted. To prevent popular items from being displaced by transient bursts, the system applies aging to counters, allowing popularity to decay over time. Some implementations employ a two-tier approach, with a hot store for commonly requested entries and a colder store for the rest.

Counter management can be exact or approximate. For large caches, approximate counters using data structures such as Count-Min sketches or aging LFU variants help keep overhead low while preserving useful frequency information. Eviction policies often blend frequency with recency to avoid bias toward long-lived but rarely reused items and to reduce cache churn.

Potential use cases include web proxies, content delivery networks, database query caches, and in-memory data stores where access patterns are highly skewed. Cacheoften can offer higher hit rates in such environments by keeping popular data readily available and discarding less useful entries more aggressively when load grows.

Advantages of cacheoften include improved cache efficiency on skewed workloads and better resilience to certain traffic patterns. Limitations involve additional metadata and processing overhead, potential cold-start penalties, and the need to tune decay rates and thresholds to reflect workload characteristics. It complements traditional policies like LRU and LFU and can be integrated with approximate counting techniques for scalable implementations.