long misses = cacheMisses.get();
        long total = hits + misses;
        
        if (total == 0) return 0.0;
        return (double) hits / total;
    }
    
    public void recordCacheHit() { cacheHits.incrementAndGet(); }
    public void recordCacheMiss() { cacheMisses.incrementAndGet(); }
    public void recordInvalidation() { cacheInvalidations.incrementAndGet(); }