SSD Controller VM Migration State Tracking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing virtual machine (VM) migration technologies involve significant downtime and resource overhead due to the need to pause and copy entire storage states, which is inefficient and disruptive to ongoing applications.
Innovation Solution
A system and method utilizing an SSD controller to track and log storage state changes during VM migration, allowing for minimal pause times by efficiently transferring only modified data, thereby reducing the blackout phase duration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the entire storage state is copied during VM migration, then data completeness is ensured, but migration time and resource overhead increase significantly
Solution Approach 1:
The patent extracts only the modified portions of storage state (dirty pages and changed metadata) rather than copying the entire storage state. The SSD controller identifies and extracts only those data blocks that have changed since the last migration or snapshot, significantly reducing the volume of data that needs to be transferred while ensuring all necessary changes are captured for data completeness.
Solution Approach 2:
The SSD controller performs preliminary tracking of storage state changes during the migration process. Before the actual migration occurs, the controller monitors and logs all modifications to the storage state, so that when migration is initiated, only the pre-identified changed data needs to be transferred, reducing migration time while maintaining data completeness.
2Reliability
If the VM is paused during migration to ensure data consistency, then data integrity is maintained, but application downtime increases
Solution Approach 1:
The patent enables continuous VM operation during migration by maintaining I/O operations throughout the process. The SSD controller captures storage state changes in real-time while the VM remains active, using change tracking mechanisms that work alongside ongoing I/O operations. This allows migration to proceed without pausing the application, though data integrity is ensured through the controller's ability to capture all modifications accurately.
Solution Approach 2:
The SSD controller acts as an intermediary that manages the complexity of maintaining data integrity during continuous operation. It mediates between the ongoing I/O operations and the migration process by tracking changes, managing buffers, and ensuring that all modifications are captured and transferred correctly, allowing the VM to remain paused for a minimal duration only when absolutely necessary.
3Speed
If more resources are allocated for migration to speed up the process, then migration speed improves, but source and destination machine resource availability decreases
Solution Approach 1:
The SSD controller performs self-service by autonomously tracking storage state changes, identifying dirty pages, and managing the data transfer process without requiring significant intervention from the source or destination VMs. This self-managed approach reduces the resource overhead on the migrating systems while maintaining high migration speed, as the storage device itself handles the complex tasks of change detection and data preparation.
Solution Approach 2:
The migration process is segmented into independent components: change tracking, data identification, data transfer, and verification. The SSD controller handles the tracking and identification segments, allowing the actual data transfer to proceed efficiently without blocking other VM operations on the source or destination machines. This segmentation enables parallel execution of migration tasks and maintains resource availability for other workloads.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A storage device is disclosed. The storage device may include at least one controller for a virtual machine (VM) (305) that is on a source host (105-1). Storage in the storage device may store data for the VM (305). A second storage may store a storage state (410) for the VM (305). A storage device controller (405) may process at least one read request received from the controller for the VM (305) using the first storage and at least one write request received from the controller for the VM (305) using the first storage. A VM migration state monitor and capture module (415) may assist in the migration of the VM (305) from the source host (105-1) to a destination host (105-2).