Separation of Storage and Compute in Cloud Databases has been an increasingly important topic for the last few years. While many databases are designed from the ground-up to achieve such a separation, ClickHouse has followed a multi-year project to slowly evolve the technology and achieve this milestone. We hope other technologies can benefit from our experience with this project.

Over the course of the last few years, we have been slowly but surely working our way to remove this limitation. This talk is the culmination of everything that was done - important fixes in the Core database as well as the cloud database Operator - to finally get rid of those volumes. Now when we allocate database server pods in the cloud - there are no Network Block Volumes attached to them. 

This talk documents the challenges of implementing such a critical feature in the journey of a cloud database, as well as the subsequent migration of customers in this cloud to this mode of operation. We will cover important topics such as S3-based Storage Engine, Catalog and S3-Plain Re-writable Disks as well as the Kubernetes Operator changes to enable these features in the Cloud.