Why Multi-Location MariaDB Galera Clusters Aren't Ideal for Write and Insert Speed

MariaDB Galera Cluster is renowned for its high availability and synchronous multi-master replication capabilities. While it excels in many scenarios, deploying Galera clusters across multiple geographical locations can lead to significant performance drawbacks, especially concerning write and insert speeds.

The Challenge of Latency

The primary issue with multi-location Galera clusters is network latency. Galera's synchronous replication means that every write operation must be confirmed by a majority of nodes before it is considered committed. When nodes are spread across different locations, the latency between them increases, leading to longer commit times.

For example, if you have nodes in New York, London, and Tokyo, the round-trip time for data to be written and confirmed across these locations can be substantial. This delay directly impacts the speed at which write and insert operations are processed, slowing down applications reliant on quick data transactions.

Impact on Write and Insert Performance

1. Increased Commit Times: Each write operation in a Galera cluster requires a global certification process, where changes are replicated and acknowledged by a majority of nodes. With high latency, the time taken for these acknowledgments increases, slowing down the overall process.

2. Transaction Conflicts: The likelihood of transaction conflicts and rollbacks increases with latency. As different nodes process writes independently before synchronization, the probability of conflicts rises, which can further degrade performance.

3. Network Reliability: Multi-location setups are more prone to network issues and instability. Any disruption in connectivity can cause nodes to lag or become temporarily unavailable, impacting the cluster's performance and consistency.

Alternatives for Multi-Location Deployments

To mitigate the performance issues associated with multi-location Galera clusters, consider the following alternatives:

1. Read-Only Replicas: Use Galera for high-availability in a single location and deploy read-only replicas in other locations. This approach allows fast reads while maintaining a central, high-performance write node.

2. Geo-Distributed Architectures: Implement a different database architecture designed for geo-distribution, such as Cassandra or CockroachDB. These databases are built to handle distributed writes with lower latency penalties.

3. Application-Level Sharding: Manually shard your database at the application level, directing writes to specific shards based on geographic or logical partitions. This method can reduce cross-location write latency but adds complexity to the application layer.

Conclusion

While MariaDB Galera Cluster is an excellent solution for high availability within a single location, its performance can degrade significantly when deployed across multiple geographical locations. The inherent latency in synchronous replication makes it less suitable for write-intensive applications spread across distant regions. By considering alternative architectures and deployment strategies, you can achieve better performance and reliability for your distributed applications.

For more information on optimizing your database architecture, visit MariaDB documentation or consult with database experts.