What databases are commonly used in multi-agent systems?

Multi-agent systems (MAS) often rely on databases that support distributed data management, high concurrency, and real-time communication between agents. Commonly used databases include Redis, Apache Cassandra, PostgreSQL, and Neo4j, each addressing specific needs like speed, scalability, or relationship handling. Decentralized databases such as OrbitDB (built on IPFS) are also gaining traction for blockchain-based MAS. These tools provide the infrastructure for agents to store, retrieve, and synchronize data efficiently while operating in dynamic environments.

Redis is widely used for its in-memory data storage and pub/sub messaging, enabling low-latency communication between agents. For example, in a traffic management system, agents representing vehicles might use Redis to broadcast their locations and receive updates about road conditions. Apache Cassandra suits scenarios requiring horizontal scalability and fault tolerance, such as large-scale IoT networks where agents collect sensor data across geographically distributed nodes. PostgreSQL, with its support for ACID transactions and JSONB data types, is ideal for systems requiring complex querying and structured data storage, like supply chain coordination platforms. Neo4j’s graph database model helps agents analyze relationships, such as social network interactions or fraud detection patterns. OrbitDB, being decentralized, is useful in trustless environments where agents operate independently, such as decentralized autonomous organizations (DAOs).

When choosing a database for MAS, developers must prioritize features like data consistency models, latency, and integration with agent frameworks. Redis sacrifices durability for speed, making it better for transient data, while PostgreSQL ensures data integrity for critical operations. Cassandra’s eventual consistency works for systems where agents tolerate temporary data mismatches. Graph databases like Neo4j add overhead but unlock insights from interconnected data. Decentralized options trade performance for resilience against single points of failure. Tools like Jason or MASON often integrate with these databases to streamline agent logic and data synchronization, ensuring the system remains cohesive under varying workloads.