Cost optimization

Transition storage classes based on access frequency and response time requirements

When a dataset is accessed less often, or when real-time access to the data is no longer required, configure appropriate lifecycle rules to automatically move the data to a lower-cost storage class without affecting access performance.

Based on the characteristics and access frequency of your data, you can filter specific objects by prefix or tag and configure lifecycle rules for them. Cold data that is rarely accessed is automatically transitioned to lower-cost Archive storage, whereas frequently accessed hot data remains in Standard storage for faster reads. This approach optimizes storage costs and improves data access efficiency.

Example

User A stores 100 TB of business data (10 million objects) under the dir directory of a bucket in the China (Hangzhou) region, using the Standard (ZRS) storage class, mainly for the company's daily operations. In the early stage of the business, the data was accessed very frequently. As the business evolved, access patterns changed. To optimize costs, User A wants to adjust the storage class of the business data at each business stage.

Early stage: all data is accessed frequently

In the early stage, the 100 TB of data is accessed an average of 5 times per month. Because access speed is critical at this point, Archive storage, which does not support real-time reads, is not suitable. User A is deciding whether to stay on Standard storage or to configure lifecycle rules that transition part of the data to Infrequent Access.

• Standard storage costs 0.15 CNY/GB/month. GET requests are free within 20 million requests and cost 0.01 CNY per 10,000 requests beyond that. No data retrieval fees apply.

• Infrequent Access costs 0.10 CNY/GB/month. GET requests cost 0.1 CNY per 10,000 requests per month per region, and the data retrieval fee is 0.0325 CNY/GB.

Cost analysis:

As the table shows, when data is accessed frequently, Standard storage wins on both cost and access speed: it keeps access efficient and avoids the extra read fees that Infrequent Access incurs. Standard storage is therefore the best choice for the business data at this stage.

Growth stage: part of the data is accessed less frequently

As the business expands, the total volume of stored data remains 100 TB, but access patterns change: 90% of the data (90 TB) is accessed only once per month, while the remaining 10% (10 TB) is still accessed frequently. To adapt to this change and keep costs under control, User A considers two strategies:

1. Stay on Standard storage: Keep the current configuration and continue to use the Standard storage class.

2. Apply lifecycle rules: Transition the data that is accessed less frequently to the more economical Infrequent Access class to reduce storage costs.

Cost analysis:

1. The cost of keeping all business data in Standard storage is calculated as follows:

   Storage class	Total data	Storage fee (CNY/month)	API request fee (CNY/month)	Data retrieval capacity fee (CNY/month)	Total fee (CNY/month)
   Standard ZRS	100 TB	15360	30	0	15390

2. Use a lifecycle rule to filter, by prefix or tag, the 90 TB of business data that is accessed an average of once per month. Configure the rule so that this data is automatically transitioned from Standard to Infrequent Access within 30 days after the last access. The remaining 10 TB of business data stays in Standard storage.

   • Standard storage: The storage fee is 0.15 CNY/GB/month. GET requests stay within 20 million requests, so no API request fee applies, and no data retrieval fee applies.

   • Infrequent Access: The storage fee is 0.10 CNY/GB/month. GET requests cost 0.1 CNY per 10,000 requests per month per region, and the data retrieval fee is 0.0325 CNY/GB.

   Storage class	Total data	Storage fee (CNY/month)	API request fee (CNY/month)	Data retrieval capacity fee (CNY/month)	Total fee (CNY/month)
   Standard ZRS	10 TB	1536	0	0	1536
   Infrequent Access ZRS	90 TB	9216	90	2995.2	12301.2

With lifecycle rules in place, the combined cost of the two storage classes is 13837.2 CNY, about 10.1% lower than using Standard storage alone. Now that access frequency has dropped, a lifecycle rule that transitions part of the business data to Infrequent Access is the ideal low-cost option: it keeps access fast while effectively controlling costs.

Recommended action:

User A can configure a lifecycle rule that automatically transitions objects matching a specified prefix from Standard to Infrequent Access within 30 days after the last access, striking a balance between cost optimization and data access speed. For detailed steps, see Lifecycle rules based on last access time.

Mature stage: cold data is retained long term

As the business matures, User A finds that some business data is used far less: it is accessed an average of once per quarter. User A confirms that access demand for this data will remain extremely low over the next few months and accepts a short restore time before the data can be read. User A therefore considers a lifecycle rule that transitions this data from Infrequent Access to Archive.

Use a lifecycle rule to filter, by prefix or tag, the 90 TB of business data that is accessed an average of once per quarter. Within 30 days after the last access, this data is automatically transitioned from Infrequent Access to Archive. The remaining 10 TB of business data stays in Standard storage because it is accessed frequently.

• Standard storage: The storage fee is 0.15 CNY/GB/month. GET requests stay within 20 million requests, so no API request fee applies, and no data retrieval fee applies.

• Archive: The storage fee is 0.033 CNY/GB/month. GET requests cost 0.1 CNY per 10,000 requests per month per region, and the data retrieval capacity fee is 0.06 CNY/GB.

As the table shows, a lifecycle rule that further transitions this business data from Infrequent Access to Archive brings the combined cost of the two storage classes to 6450.3 CNY, another 53.4% lower than transitioning to Infrequent Access alone, for a much more significant cost saving.

Recommended action

If your access patterns are known and stable, specify all objects that match a prefix in the rule, and change the configuration so that objects are automatically transitioned from Standard to Infrequent Access within 30 days after the last access, and from Infrequent Access to Archive 60 days after the last access. Objects then move from Standard to Infrequent Access 30 days after the last access and to Archive 30 days later, which achieves the lowest storage cost. For detailed steps, see Lifecycle rules based on last access time.