Conflict Resolution Strategies
In replicated systems, conflicts occur when multiple replicas make concurrent updates to the same data. Effective conflict resolution strategies are essential to maintain data consistency and integrity. Common strategies include:
- Last-Write-Wins (LWW): The most recent update based on a timestamp is chosen as the correct one. Simple to implement. Systems with low update conflicts, such as caching and simple data stores.
- Version Vectors: Each update is tagged with a version vector to track causality between updates. Provides a detailed history of updates, helping to resolve conflicts more accurately. Distributed databases and collaborative applications where understanding the order of operations is crucial.
- Operational Transformation (OT): Concurrent updates are transformed to be compatible with each other. Maintains the intention of all operations, ideal for real-time collaboration. Editing tools for collaboration, like Google Docs.
- Application-Specific Logic: Custom conflict resolution logic based on business rules or application needs. Customized to meet the unique needs of the application. E-commerce systems, inventory management.
Replication in System Design
Replication in system design involves creating multiple copies of components or data to ensure reliability, availability, and fault tolerance in a system. By duplicating critical parts, systems can continue functioning even if some components fail. This concept is crucial in fields like cloud computing, databases, and distributed systems, where uptime and data integrity are very important. Replication enhances performance by balancing load across copies and allows for quick recovery from failures.
Important Topics for Replication in System Design
- What is Replication?
- Importance of Replication
- Replication Patterns
- Data Replication Techniques
- Consistency Models in Replicated Systems
- Replication Topologies
- Consensus Algorithms in Replicated Systems