RCU/WCU – NoSQL database throughput metrics for reads and writes.
These are throughput capacity metrics used primarily in AWS DynamoDB and similar NoSQL databases. One RCU represents one strongly consistent read per second (or two eventually consistent reads) for items up to 4KB. One WCU represents one write per second for items up to 1KB. Understanding RCU/WCU requirements is crucial for proper capacity planning and cost management in NoSQL deployments. Cloud providers offer both provisioned and on-demand capacity modes, allowing users to choose between predictable performance with provisioned capacity or pay-per-use with on-demand capacity.
