When you use Block Storage, you are charged for the pre-configured storage capacity even if the disk is not attached or only few write operations are performed on the disk. Therefore, to optimize the performance and cost of Block Storage, you must regularly monitor and identify cloud disks that are underused, overused, and not attached, and adjust the capacity of these disks to meet actual requirements.
Delete cloud disks that are not attached or used
The simplest way to reduce storage cost is to find and delete cloud disks that are not attached to ECS instances. If a cloud disk is not released when the ECS instance to which the disk is attached is stopped or terminated, the cloud disk is not automatically deleted and continues to incur fees. In this case, you must manually delete the cloud disk. You can also check whether read and write operations are performed on a cloud disk in the past few weeks. If a cloud disk in non-production environments is not used for several weeks or not attached to a ECS instance for one month, we recommend that you delete the disk in a timely manner.
Adjust cloud disk capacity
For a overused cloud disk, you can scale up the disk online or offline to increase the capacity of the disk. For enhanced SSDs (ESSDs), you can upgrade the performance level (PL) of the disk online to meet your requirements on performance and capacity.
You can downgrade the PL of a pay-as-you-go ESSD online to reduce storage capacity and cost.
You can also re-initialize a cloud disk to restore the disk to the state when it was created.
Delete old snapshots
If you create an automatic snapshot policy that takes snapshots on a daily or weekly basis, a large number of snapshots are created and stored. You must regularly clean up unnecessary snapshots to reduce storage costs. You can set a retention period for snapshots in automatic snapshot policies to automatically delete snapshots that exceed the retention period. The deletion of snapshots does not affect Block Storage.