In this detailed exploration of Couchbase cluster sizing, the author delves into the influence of application designs and workloads on the five key factors: RAM, disk, CPU, network, and data distribution. The text highlights the transition from Couchbase Server 1.8 to 2.0, noting the added complexity due to new features like Cross Datacenter Replication (XDCR) and views for indexing and querying. It emphasizes the need for careful consideration of RAM and disk requirements, particularly when dealing with XDCR, which increases both CPU and disk IO demands. The discussion also covers the impact of the new view system on disk space, IO, and CPU usage, stressing the importance of best practices in view design to mitigate resource strain. Rebalancing with views requires additional RAM, disk space, and IO, but benefits from having more nodes. Overall, the piece underscores the importance of tailoring cluster sizing to specific application needs and testing thoroughly in production environments.