Online Deduplicated Data Migration

In storage systems, the data migration process periodically remaps files between volumes with the goal of preserving the system’s load balance and deduplication efficiency. Previous studies focused on offline selection of files to migrate, a task complicated by the inter-file dependencies introduced by deduplication. However, they did not address the possibility of files entering and leaving the system due to user actions, nor the order between individual file transfers. Our motivational study reveals that naïve ordering may create traffic spikes and leave the system in poorly balanced intermediate states. To address these challenges, we present Slide—a novel online migration approach based on sliding windows. Slide takes advantage of long-term planning to maximize deduplication efficiency while maintaining short-term load balance and adapting to system changes. It achieves superior load balancing than alternative approaches while incurring minimal increase in the overall system size.

M.Sc. student under the supervision of Prof. Gala Yadgar.