CacheSystem

CacheSystem is a software or hardware mechanism that stores copies of data from a primary data store in a faster-access storage layer to reduce latency, improve throughput, and decrease load on the underlying source. It is used across computing domains, including CPUs, databases, web servers, and distributed applications.

In practice, a CacheSystem selects which data to store, how long to keep it, and when to refresh or evict items. Storage options include in-memory caches for speed and distributed caches that span multiple processes or machines. Data is identified by keys and serialized for storage, and cache clients interface with the cache store via APIs. Many implementations support time-to-live semantics, write-through and write-behind updates, and cache warming.

Eviction policies determine what data to remove when space is needed. LRU and LFU are common, with FIFO and other variants. Invalidation and consistency mechanisms vary by use case, using TTLs, explicit invalidation, or event-driven refreshes. Coherence models range from strong to eventual consistency in distributed contexts.

Typical architectures include local or in-process caches for a single application, remote or distributed caches serving multiple clients, and multi-tier setups that complement databases and content delivery networks. Read-through and write-through patterns are common in enterprise deployments.

Popular implementations include Memcached, Redis, Ehcache, Caffeine, and Apache Ignite. Design considerations include data size, latency requirements, durability, fault tolerance, and security. Monitoring metrics such as cache hit rate, miss rate, and eviction count guide tuning.