Reserved read/write throughput is an attribute of tables for high-performance instances. The system reserves resources based on the reserved read/write throughput configurations for the table to meet the throughput demand of the table.

You must specify reserved read /write throughput when you create a table for high-performance instances. After the table is created, you can call the UpdateTable operation to update the reserved read /write throughput configurations.

The reserved read and write capacity units (CUs) for a single table can be set to a value greater than or equal to 0. By default, the maximum values for read and write CUs cannot exceed 100,000. To use more than 100,000 reserved read CUs or 100,000 reserved write CUs, click here to submit a ticket and increase reserved read CUs or reserved write CUs.

Fees are generated even if the reserved read or write throughput is set to 0 and no requests are sent to read data from or write data to the table.

CU is the unit to measure the consumed resources of reserved read and write throughput. Read and write CUs are consumed when you use an application to call an operation to read data from or write data to a Tablestore table.

Tablestore charges the fees generated on an hourly basis based on the sum of reserved read and write CUs for high-performance instances of all tables in an account. The specified reserved read and write CUs can be modified. Tablestore collects statistics for the total reserved read CUs and write CUs of tables at predetermined intervals, calculates average reserved read CUs and write CUs per hour, and calculates fees by multiplying the average total reserved read CUs and write CUs per hour by the unit price. The unit price of reserved read CUs and write CUs may change. For more information about pricing, see Tablestore Pricing.