Managing data store locality at scale with Akkio

Introduced Akkio, a new data placement service (DPS) designed to optimize data retrieval speed and reduce storage and network costs in geo-distributed data centers. Akkio operates at a microshard granularity, determining optimal data placement based on access patterns and available capacity. It addresses the limitations of traditional caching for Facebook's workloads by handling strong consistency requirements and high write volumes more effectively. The system leverages ZippyDB for storing access patterns and metadata, and serializes migrations through locks to prevent concurrent operations.