The blog post provides an overview of Couchbase's new Magma storage engine, comparing it with the existing Couchstore engine, and detailing performance benchmarks. Couchstore is optimized for high performance with datasets that fit in memory, requiring a minimum bucket size of 100MB, making it ideal for caching use cases. In contrast, Magma is designed for large datasets that exceed memory limits, optimizing for disk access and high data density with a minimum bucket memory quota of 1GB. Magma's architecture includes features such as scalable concurrent compactions and SSD optimization, aiming to reduce write amplification and extend SSD lifespan. Performance tests using Yahoo! Cloud Serving Benchmark workloads revealed that Magma significantly outperformed both Couchstore and RocksDB in write-heavy scenarios, achieving faster throughput and reduced write amplification. The improved efficiency of Magma has increased the data density supported by Couchbase Server and decreased memory requirements, ultimately lowering the total cost of ownership.