Coarse-Grained Volume Snapshots for VM Backup
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing virtual machine backup and restore techniques face challenges in minimizing performance impact and virtual disk footprint, particularly due to the inefficiencies of conventional snapshot mechanisms that transform content into read-only formats and require I/O-intensive merge operations for restore processes.
Innovation Solution
The implementation of coarse-grained volume snapshots using hardware-assisted volume snapshot technology, where only dirty blocks are copied from source volumes to thin-provisioned target volumes, allowing for efficient backup and restore operations with reduced I/O operations and storage footprint.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional snapshot mechanisms are used to backup virtual machine volumes, then backup capability is provided, but performance impact on hypervisors and VMs increases and virtual disk footprint expands
Solution Approach 1:
The patent segments the backup process by identifying and copying only dirty blocks (modified blocks) from source volumes to target volumes, rather than copying entire volumes. This segmentation of data into clean and dirty blocks reduces the amount of data processed during backup operations, minimizing performance impact on hypervisors and VMs while maintaining reliable backup capability
Solution Approach 2:
The patent extracts only the necessary data elements (dirty blocks) from the source volume for backup purposes, leaving the majority of clean blocks untouched. This extraction approach reduces I/O operations during backup and restore, thereby reducing performance impact while ensuring backup reliability through selective copying of changed data
2Reliability
If conventional snapshot mechanisms are used to backup virtual machine volumes, then backup capability is provided, but virtual disk footprint increases
Solution Approach 1:
The patent segments the volume data into dirty and clean blocks, and only allocates storage space for dirty blocks in the target volume. This segmentation enables the backup system to maintain reliable backup capability while minimizing virtual disk footprint by storing only the changed portions of data rather than entire volume copies
Solution Approach 2:
The patent changes the storage allocation parameter from fixed full-volume allocation to dynamic dirty-block-only allocation. By tracking which blocks have been modified and allocating storage only for those blocks, the system reduces virtual disk footprint while maintaining complete backup capability through selective data preservation
3Reliability
If conventional snapshot mechanisms are used for restore operations, then restore capability is provided, but I/O-intensive merge operations are required
Solution Approach 1:
The patent extracts only the dirty blocks from the target volume during restore operations and copies them directly to replace the corresponding blocks in the source volume. This extraction approach eliminates the need for complex merge operations that would be required in conventional snapshot mechanisms, simplifying the restore process while ensuring data integrity and restore capability
Data Source
AI summary
A technique of backing up a workload in a virtual environment includes identifying one or more files that are associated with the workload. One or more source volumes that include the one or more files are identified. A respective target volume is provisioned for each of the one or more source volumes identified. Only dirty blocks are copied (in a snapshot mode that prevents an update to the one or more source volumes during the snapshot mode) from each of the one or more source volumes to its respective target volume. The one or more dirty blocks are then copied from each target volume to a backup medium.