CockroachDB vs Galera Cluster: What are the differences?

Introduction

CockroachDB and Galera Cluster are two popular database management systems that offer high availability and scalability. While both solutions provide distributed architecture, there are key differences between them. This article highlights six differences that set CockroachDB and Galera Cluster apart.

1. Transaction model: CockroachDB uses a distributed ACID (Atomicity, Consistency, Isolation, Durability) transaction model, ensuring that transactions are executed reliably across clusters. On the other hand, Galera Cluster employs a synchronous multi-master replication model, allowing each node to execute transactions independently and replicate them to other nodes.

2. Consistency model: CockroachDB follows strict serializable consistency for transactions, making it suitable for applications that require strong data consistency. Galera Cluster, on the other hand, employs the optimistic concurrency control model, which allows multiple concurrent transactions, but may result in occasional conflicts that need to be resolved.

3. Resiliency: CockroachDB is designed for resilience, offering automatic data replication and fault tolerance across multiple nodes. It can handle node failures without affecting the overall system. Galera Cluster, although resilient, requires manual intervention to handle node failures and maintain cluster consistency.

4. Sharding: CockroachDB natively supports automatic data sharding, distributing data across multiple nodes for improved performance and scalability. Galera Cluster requires manual configuration and management of sharding techniques such as horizontal partitioning.

5. Geo-distribution: CockroachDB excels in geo-distributed deployments, allowing data to be replicated across multiple regions with low latency. Galera Cluster is better suited for deployments within a single data center or close geographical proximity due to the need for synchronous replication.

6. Operational complexity: CockroachDB simplifies operations with its built-in automated management and scaling features. It offers self-healing capabilities and can automatically rebalance data. Galera Cluster, being more complex, requires manual management and configuration of clusters, which can be challenging for less experienced administrators.

In summary, CockroachDB's ACID compliance, strict consistency model, automatic sharding, and simplified management make it a versatile option for distributed databases. On the other hand, Galera Cluster provides multi-master replication, optimistic concurrency control, and flexibility for deployments within a single data center, but requires more manual intervention and is less suitable for geo-distributed setups.