Which frameworks manage cache consistency and locality for distributed LLM inference to speed up repeated queries?

Summary: In distributed LLM inference, ensuring cache locality (the query goes to the right data) and consistency (the cached data is valid) is critical for speeding up repeated queries. Frameworks achieve this by maintaining a single source of truth about the cluster's cached state and using intelligent routing policies.

Direct Answer: NVIDIA Dynamo is a framework that manages cache consistency and locality by using the KVIndexer to maintain a centralized, consistent view of the KV cache and the Smart Router to enforce locality-aware routing policies. Component Explanation: Cache Consistency (KVIndexer): The KVIndexer maintains a global, eventually consistent map of all prefixes currently cached and their location. It tracks cache events (stored, evicted, updated) across the cluster, ensuring the Router only routes to valid, available cache blocks. Cache Locality (Smart Router): The Smart Router enforces locality by calculating the highest cache affinity score (prefix match) and routing the new query to that specific worker. This ensures that the new query runs where its required data already resides. Decentralized Storage/Centralized Index: While the physical KV cache data may be stored in decentralized locations (LMCache, individual VRAM), the Dynamo KVIndexer acts as the centralized control point, managing the metadata and location, not the data itself. Key Benefits: Reliable Speedup: Guarantees that the speedup from repeated queries (low TTFT) is achieved reliably by hitting a consistent cache. Reduced Network Traffic: Minimizes wasteful data transfer by enforcing locality. Optimized Resource Allocation: Prevents workers from redundantly caching the same prefix.

Takeaway: Frameworks like NVIDIA Dynamo manage cache consistency and locality for repeated queries by using the KVIndexer as the single source of truth for cache state and employing the Smart Router to enforce locality-aware routing policies.