Snapshot Volume Synchronization via Valid Region Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Standard synchronization mechanisms for virtual machine snapshots are inefficient, leading to larger remote copies and increased network bandwidth usage, and can take a long time to complete.
Innovation Solution
The solution involves writing data blocks to a snapshot before overwriting them, and synchronizing only the valid regions of the snapshot across hosts, ensuring that only the changed data is sent, thereby optimizing storage and bandwidth usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If standard synchronization mechanisms are applied to snapshots, then the remote copy can be kept up-to-date, but the remote copy may end up being larger than the source version
Solution Approach 1:
The patent extracts only the valid regions (changed data blocks) from the snapshot for synchronization, leaving the invalid regions (unchanged data) on the primary host. This selective extraction prevents the remote copy from including redundant unchanged data, resolving the contradiction between maintaining synchronization reliability and controlling remote copy size.
Solution Approach 2:
The snapshot is segmented into valid regions and invalid regions based on data change status. By identifying and separating the valid regions that contain actual changes from the invalid regions with unchanged data, the system can synchronize only the necessary portions, preventing remote copy bloat while maintaining synchronization integrity.
2Reliability
If standard synchronization mechanisms are used for snapshots, then the remote copy can be synchronized, but it can take a relatively long time to complete
Solution Approach 1:
The patent extracts only the valid regions (changed data blocks) from the snapshot for synchronization. By sending only the changed portions rather than the entire snapshot, the data transfer time is significantly reduced while the remote copy remains properly synchronized, resolving the time-reliability contradiction.
Solution Approach 2:
Instead of synchronizing the complete snapshot, the patent applies partial action by synchronizing only the valid regions that contain actual data changes. This partial synchronization approach reduces the time required while still achieving the goal of keeping the remote copy up-to-date.
3Reliability
If standard synchronization mechanisms are applied to snapshots, then the remote copy can be kept up-to-date, but it can consume a relatively large amount of network bandwidth
Solution Approach 1:
The patent extracts and transmits only the valid regions (changed data blocks) over the network, rather than sending the entire snapshot. This selective data extraction dramatically reduces network bandwidth consumption while ensuring the remote copy remains synchronized with the source.
Solution Approach 2:
The patent applies partial action by transmitting only the necessary valid regions that contain data changes,而非 the complete snapshot. This partial data transmission reduces network bandwidth consumption while maintaining synchronization reliability.
Data Source
AI summary
Prior to overwriting a block of data in a first volume of data on a primary host, the block of data is written to a first snapshot of the first volume. Subsequently, the first snapshot can be synchronized with a snapshot of a second volume of data on a secondary host, where the second volume is a replica of the first volume. To synchronize the snapshots, only a portion of the first snapshot (e.g., the block of data that was written to the first snapshot) is sent to the secondary host.