v3.40.1 fixed the eviction formula but fairness parameters were too gentle,
allowing metadata to regenerate faster than eviction could keep up. This
caused cache thrashing: evict 20% → regenerate → evict 20% → repeat.
Changes to prevent thrashing:
1. Fairness interval: 60s → 30s (faster response to imbalances)
2. Size threshold: 90% → 70% (earlier intervention)
3. Access threshold: <10% → <15% (catch more imbalances)
4. Eviction amount: 20% → 50% (more aggressive cleanup)
5. Proactive checking: Added immediate fairness check during set() operations
to prevent imbalance formation rather than just reacting to it
This should eliminate the "still creating relationships" slowdown reported
by Soulcraft Studio while maintaining the OOM crash prevention from v3.40.1.
Fixed inverted eviction scoring formula in UnifiedCache that was causing
metadata (cheap to rebuild) to be retained while HNSW vectors (expensive,
frequently accessed) were evicted. This was causing OOM crashes during
large Excel imports with relationship extraction.
Changes:
- evictLowestValue(): Changed accessScore / rebuildCost to accessScore * rebuildCost
- evictForSize(): Changed accessScore / rebuildCost to accessScore * rebuildCost
- evictType(): Changed accessScore / rebuildCost to accessScore * rebuildCost
With the corrected formula, items with higher access counts AND higher
rebuild costs get higher scores and are protected from eviction.
Test coverage: Added comprehensive eviction scoring tests
Fixes: Type metadata hogging 99.7% of cache with only 3.7% access rate