EvictionPolicies LRU LFU FIFO
When a cache is full, which entry gets removed to make room? LRU (least recently used), LFU (least frequently used), and FIFO (oldest inserted) are the standard eviction policies — a different concern from the read/write population strategies (cache-aside/write-through/etc.).
Why we need this / what value this brings
A cache with the wrong eviction policy either evicts data you're about to need again (hurting hit rate) or wastes memory holding data nobody wants anymore.
When to use this
Whenever a cache has a fixed size limit and needs to decide what to remove when full — every production cache eventually hits this.
How to use or implement this
LRU is the right default for most access patterns (recently used data tends to be used again); use LFU only when access frequency is a better predictor of future use than recency, and FIFO only when simplicity matters more than hit-rate optimization.
Research questions
- Most managed caches (Redis with maxmemory-policy) let you pick this — has it ever been explicitly set for Localz's cache, or is it running on a default that may not fit the access pattern?
Empty folder — drop notes, links, and findings here as you research.