Resizing a cluster refers to changing the compute power and RAM to optimize concurrency. When you resize a cluster, the amount of VCPUs and RAM allocated to it is adjusted based on the new cluster size you specified. For more information and use cases, see Database Scalability. This page describes how to resize a cluster in the web console.
You can resize a running or stopped cluster.
Resizing a cluster while it is running will automatically restart that cluster. If the cluster you are resizing is the MAIN cluster, then the database and all clusters will be restarted and unavailable during the scaling operation.
A stopped cluster will not automatically restart after being resized. You must start the cluster. For more information, see Start and Stop a Cluster.