Cascaded Snapshot Parent Deletion via Data Migration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In conventional data backup methods, deleting a parent snapshot with a child snapshot is not allowed, leading to resource wastage as the child snapshot cannot be deleted independently, causing data reading failures.
Innovation Solution
A method that migrates data from the parent snapshot to the child snapshot, allowing the parent snapshot to be deleted while ensuring the child snapshot's data integrity is maintained by setting unique timestamps and distinguishing between copy-on-write and private data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a parent snapshot is deleted while having child snapshots, then resource usage is optimized, but data reading failures occur in child snapshots
Solution Approach 1:
The patent extracts the parent snapshot from the cascaded snapshot chain by migrating its data to child snapshots. When a parent snapshot needs to be deleted, its data is copied to the child snapshots, allowing the parent to be removed independently without affecting child snapshot functionality. This resolves the contradiction by enabling resource optimization through deletion while maintaining data reading integrity in child snapshots.
2Reliability
If child snapshots retain parent snapshot data, then data integrity is maintained, but resource waste occurs when parent snapshots are no longer needed
Solution Approach 1:
The patent implements dynamic data management in cascaded snapshots by enabling flexible deletion of parent snapshots regardless of child snapshot existence. The system dynamically adjusts the snapshot hierarchy by migrating data as needed, allowing parent snapshots to be deleted when no longer needed while child snapshots maintain their data integrity through the migration mechanism. This resolves the contradiction by making the snapshot structure dynamic rather than static.
3Ease of operation
If data is migrated from parent snapshot to child snapshot, then parent snapshot can be deleted independently, but system complexity increases
Solution Approach 1:
The patent uses child snapshots as intermediary structures to facilitate parent snapshot deletion. The child snapshots serve as mediators that receive migrated data from parent snapshots, enabling the parent to be deleted independently. This intermediary mechanism simplifies the deletion operation while managing the complexity through a structured migration process that maintains system integrity.
Data Source
Figure 1~3
Figure 4~5
Figure 6A
AI summary
The present invention discloses a method and an apparatus for deleting a cascaded snapshot. The method is applied to a storage device, the storage device includes a logical volume, and the logical volume corresponds to a plurality of cascaded snapshots including at least a first snapshot, a second snapshot, and a third snapshot. The second snapshot is a parent snapshot of the first snapshot, and the third snapshot is a child snapshot of the first snapshot. When an instruction for deleting the first snapshot is received (401), where the first snapshot includes target data. Information of the target data is migrated to the second snapshot (402), where the information of the target data includes a timestamp of the first snapshot, and the timestamp of the first snapshot is set when the first snapshot is created. A parent snapshot identifier corresponding to the third snapshot is set to an identifier of the second snapshot (403), where the set parent snapshot identifier corresponding to the third snapshot indicates that a parent snapshot of the third snapshot is the second snapshot. The first snapshot is deleted (404).