Conflict-Free Replicated Data Types (CRDTs)
In distributed systems, keeping data consistent across multiple nodes without sacrificing availability and performance is a challenging problem. When multiple users or services update the same piece of data simultaneously, traditional approaches like locks, transactions, or consensus algorithms (Paxos, Raft) introduce overhead, latency, and single points of failure.
What if we could ensure eventual consistency while allowing concurrent modifications without conflicts?
This is where CRDTs (Conflict-Free Replicated Data Types) come in. CRDTs allow multiple replicas to independently update data and then merge changes without conflicts. They are used in systems like Google Docs, Redis, Riak, and DynamoDB for handling real-time collaboration, distributed caches, and multi-region databases.
In this article, we will explore:
- Why CRDTs are needed
- How CRDTs work
- Types of CRDTs
- Real-world applications
- Code implementation