October 31, 2025
Cache me outside, how ’bout dat
Value-pool based caching for Java applications
New Java cache promises one update to fix them all, commenters ask: 'But what is it?'
TLDR: Mnemosyne is a new Java cache that updates one object and syncs all related caches at once. Commenters are intrigued but confused, asking for clearer docs, safety guarantees, benchmarks, and comparisons to existing caches; fans love the concept, skeptics want proof before trusting production data.
Meet Mnemosyne, a new Java caching library that claims a simple magic trick: update one object and every related cache across your app syncs instantly. It pools values by ID in memory, ships with FIFO and LRU (what’s LRU?), and currently plugs into Spring. Devs can even swap in their own strategies. Sounds slick—until the comments rolled in and asked, loudly, what it actually does.
The top vibe: intrigue mixed with confusion. One early reader called the write-up “useful but confusing,” peppering the thread with “are we caching lists or objects or types?” energy. The diagram? “Not helping.” The mood turned spicy around safety and clarity: folks wanted to hear about memory and thread guarantees, how this avoids leaks, and whether eviction policies are tunable in the real world. Cue the classic meme: cache invalidation is one of the two hard problems—so why trust a new one without benchmarks? Others questioned why not just use Caffeine or Ehcache, while fans cheered the “update once, fix everywhere” idea as a legit quality-of-life win. “Works with Spring” sparked a mini framework war: Spring stans: thrilled; everyone else: “call us when Micronaut/Quarkus join.” And yes, the name Mnemosyne (goddess of memory) inspired jokes that a memory library better not forget its docs. Drama, delivered.
Key Points
- •Mnemosyne is a Java cache library under development and testing as of October 2025.
- •It uses a shared Value Pool per type, with method caches storing IDs instead of object values.
- •Updates to an object propagate to the Value Pool, synchronizing all related caches at once.
- •Developers can extend an abstract class for domain-specific caching; default FIFO and LRU are provided.
- •Mnemosyne currently integrates with Spring, with plans for additional integrations.