Galera Cluster vs Scylla: What are the differences?

## Introduction

Key differences between Galera Cluster and Scylla are outlined below:

1. **Consistency Model:** Galera Cluster ensures strong consistency where all nodes in the cluster have the same data at the same time, while Scylla follows an eventually consistent model, allowing for faster writes and higher availability.
   
2. **Underlying Technology:** Galera Cluster is based on the MySQL replication protocol, providing synchronous replication, whereas Scylla is built on the Apache Cassandra model, utilizing a highly optimized architecture for write-heavy workloads.
   
3. **Data Distribution:** Galera Cluster employs a multi-master setup where all nodes can accept both read and write requests, whereas Scylla uses a masterless architecture with each node capable of both reading and writing data independently.
   
4. **Query Language Support:** Galera Cluster is compatible with SQL databases like MySQL, while Scylla supports CQL (Cassandra Query Language) for interacting with the database.
   
5. **Performance:** Galera Cluster demonstrates strong performance for read-heavy workloads due to its synchronous replication, while Scylla is optimized for write-heavy workloads with high throughput and low latency.
   
6. **Management Complexity:** Galera Cluster requires careful configuration and maintenance to ensure proper synchronization among nodes, while Scylla offers simpler management with automatic sharding and decentralized data distribution.

## Summary
In summary, the key differences between Galera Cluster and Scylla lie in their consistency model, underlying technology, data distribution, query language support, performance characteristics, and management complexity.