This topic describes problems you may encounter when you use the versioning feature and provides troubleshooting methods and solutions.
Storage costs
If you enable versioning for a bucket, you are charged for the storage of the current versions and previous versions of all objects in the bucket. The following example is used to describe the storage costs incurred in a 30-day month for a versioning-enabled bucket.
Assume that on the first day of the month, you upload an object that is 20 GB in size by calling the PutObject operation and set the storage class of the object to Standard (locally redundant storage).
On the sixteenth day of the month, you write 40 GB of data to the object by calling the PutObject operation.
Note that when you write 40 GB of data on day 16, the 20 GB object that you uploaded on day 1 is not deleted. Instead, the 20 GB object is retained as a previous version for 30 days, and the 40 GB object becomes the current version, stored for 15 days.
Under the pay-as-you-go billing rules, the monthly storage cost is: 20 GB × CNY 0.12/GB/month + 40 GB × CNY 0.12/GB/month ÷ 30 days × 15 days = CNY 4.8.
For more information about storage costs for different storage classes, see Storage fees.
Low response speed
Problem description: The response to a GetBucket (ListObjects) operation on a versioning-enabled bucket significantly slows down.
Cause: One or more objects in your bucket have a large number of previous versions or expired delete markers.
Troubleshooting:
Call the GetBucketVersions (ListObjectVersions) operation to check whether objects in your bucket have a large number of versions. For more information, see ListObjectVersions (GetBucketVersions).
Use the bucket inventory feature to view information about objects in your bucket and check whether the objects have previous versions or expired delete markers. For more information, see Bucket inventory.
Solution: Configure a lifecycle management rule to expire previous versions by using the NonCurrentVersionExpiration action and remove expired delete markers by using the ExpiredObjectDeleteMarker action. For more information, see Configuration elements.
Data size exception
Problem description: The total object size shown on the Objects page of a bucket is inconsistent with the total storage capacity on the Overview page of the bucket.
Cause: You have enabled versioning. After versioning is enabled, click Show on the file list page to display previous versions. The total size of all files will then match the total storage on the Bucket overview page.