Billing for Tair Serverless KV | Pricing | Tair - Tair (Redis® OSS-Compatible)

Tair Serverless KV is billed based on compute resource fees (RCU/WCU) and storage space fees.

Billable items

Compute resource consumption (pay-per-operation)

Read operations (RCU): One Read Capacity Unit (RCU) is consumed for every 4 KB of data read in a request. A read operation for data smaller than 4 KB is counted as 4 KB.
Example: Reading 1 KB or 4 KB of data consumes 1 RCU. Reading 7 KB (4 KB + 3 KB) of data consumes 2 RCUs.
Write operations (WCU): One Write Capacity Unit (WCU) is consumed for every 512 B of data written in a request. A write operation for data smaller than 512 B is counted as 512 B.
Example: Writing 200 B of data consumes 1 WCU. Writing 1 KB (1024 B = 512 B × 2) of data consumes 2 WCUs. Writing 1.2 KB (1228 B ≈ 512 B × 2.4) of data consumes 3 WCUs.

Examples of CU calculations for common commands

Category	Calculation rule
Scan-type commands for primary keys (SCAN, KEYS)	1 base RCU + RCUs calculated based on the actual scanned key size
General commands (such as DEL, EXISTS)	n WCUs are calculated based on the number of keys (n)
KV structure (such as String)	Write (such as SET)	Key does not exist	WCUs are calculated based on key size + value size
	Write (such as SET)	Key exists	The operation is divided into a query phase and a write phase. In the query phase, RCUs are calculated based on the key size. In the write phase, WCUs are calculated based on the key size + value size.
	Read (such as GET)	Key does not exist	1 RCU is consumed
	Read (such as GET)	Key exists	RCUs are calculated based on key size + value size
KKV structure (such as Hash, Set, Zset, List, Geo)	Write (such as HSET)	Key does not exist	WCUs are calculated based on key size + field size + value size
		Key exists, but field does not exist	The system first looks up the key, which consumes RCUs based on the key size. Then, it calculates WCUs based on key size + field size + value size.
		Key and field exist	The system first looks up the key, which consumes RCUs based on the key size. Then, it looks up the field, which consumes RCUs based on key size + field size + old value size. Finally, it calculates WCUs based on key size + field size + value size.
	Read (such as HGET)	Key does not exist	1 RCU is consumed
		Key exists, but field does not exist	RCUs are calculated based on the key size
		Key and field exist	RCUs are calculated based on the key size, and then more RCUs are calculated based on key size + field size + value size.
	Scan-type commands (such as HSCAN)	Key does not exist	1 RCU is consumed
	Scan-type commands (such as HSCAN)	Key exists	2 base RCUs, plus RCUs calculated based on the scanned field size + value size (if a value is returned)

Storage space usage
Billing is based on the actual storage space that the instance uses, measured in GB. Usage is measured hourly. If the usage is less than 20 GB, it is billed as 20 GB. If the usage is more than 20 GB, it is rounded up to the nearest integer GB.
Example: 15 GB of storage is billed as 20 GB. 50.2 GB of storage is billed as 51 GB.

Pricing

Available regions	RCU	WCU	Storage
China North 2 (Beijing), China East 2 (Shanghai), China East 1 (Hangzhou), China South 1 (Shenzhen)	USD 0.086 per million requests	USD 0.13 per million requests	USD 0.00029 per GB-hour
Indonesia (Jakarta), Singapore	USD 0.1 per million requests	USD 0.15 per million requests	USD 0.00035 per GB-hour

Billing methods

Billable item	RCU	WCU	Storage
Usage statistics	The system calculates the number of RCUs and WCUs that the instance consumes every second. The total consumption is aggregated daily. Billing is in units of one million requests. Usage is rounded up to the nearest million.		The system calculates the average hourly storage usage in GB for the instance. If the usage is less than 20 GB, it is billed as 20 GB. The total consumption is aggregated daily. Billing is in units of GB. Usage is rounded up to the nearest integer.
Daily fee calculation formula	Fee = (ROUNDUP(Total daily consumption / 1,000,000)) × Unit price		Fee = (Sum of hourly storage usage in GB for the day) × Unit price
Billing cycle	Daily		Daily

Billing examples

Example 1: An instance in the China North 2 (Beijing) region consumes 1.1 million RCUs and 0.2 million WCUs in a day. The storage usage is 30 GB for 18 hours and 50 GB for 6 hours.
- RCU fee: 1.1 million requests are billed as 2 million requests. Fee: 2 million × USD 0.086/million = USD 0.172
- WCU fee: 0.2 million requests are billed as 1 million requests. Fee: 1 million × USD 0.13/million = USD 0.13
- Storage fee:
  - 30 GB for 18 hours: 30 GB × 18 hours = 540 GB-hours.
  - 50 GB for 6 hours: 50 GB × 6 hours = 300 GB-hours.
  - Total storage fee: (540 GB-hours + 300 GB-hours) × USD 0.00029/GB-hour = USD 0.2436
- Total daily fee: USD 0.172 (RCU) + USD 0.13 (WCU) + USD 0.2436 (Storage) = USD 0.5456.
Example 2: An instance in the China East 2 (Shanghai) region consumes 11.8 million RCUs and 5.3 million WCUs in a day. The storage usage is 500 GB for 6 hours, 450 GB for 13 hours, and 600 GB for 5 hours.
- RCU fee: 11.8 million requests are billed as 12 million requests. Fee: 12 million × USD 0.086/million = USD 1.032
- WCU fee: 5.3 million requests are billed as 6 million requests. Fee: 6 million × USD 0.13/million = USD 0.78
- Storage fee:
  - 500 GB for 6 hours: 500 GB × 6 hours = 3,000 GB-hours.
  - 450 GB for 13 hours: 450 GB × 13 hours = 5,850 GB-hours.
  - 600 GB for 5 hours: 600 GB × 5 hours = 3,000 GB-hours.
  - Total storage fee: (3,000 GB-hours + 5,850 GB-hours + 3,000 GB-hours) × USD 0.00029/GB-hour = USD 3.4365
- Total daily fee: USD 1.032 (RCU) + USD 0.78 (WCU) + USD 3.4365 (Storage) = USD 5.2485.