Storage in Amazon Keyspaces

Amazon Keyspaces (for Apache Cassandra) provisions storage to tables automatically based on the actual data stored in your table. You do not need to provision storage to tables upfront. Amazon Keyspaces scales your table storage up and down automatically as your application writes, updates, and deletes data. Unlike traditional Apache Cassandra clusters, Amazon Keyspaces does not require additional storage to support low-level system operations such as compaction. You pay only for the storage you use.

Amazon Keyspaces configures keyspaces with a replication factor of three by default. You cannot modify the replication factor. Amazon Keyspaces replicates table data three times automatically in multiple AWS Availability Zones for high availability. The per-GB price of Amazon Keyspaces storage already includes replication. See Amazon Keyspaces (for Apache Cassandra) Pricing for more information.

Amazon Keyspaces monitors the size of your tables continuously to determine your storage charges. For more information about how Amazon Keyspaces calculates the billable size of the data, see Calculating row size in Amazon Keyspaces.