Live virtual machine migration with optimized three-stage memory copy

Abstract

Live virtual machine migration has become an important management method in clusters and data centers. It allows application isolation and facilitates server consolidation, load balancing, fault management and power saving. Existing live migration approaches pre-copy have to iteratively copy redundant memory pages, another approach post-copy would lead to a lot of page fault and application degradation. This paper presents the detail design of a novel three-stage memory copy live migration approach. Memory pages only need to be transmitted twice at most, and page fault just occurred in small part of dirty pages. We implement it in Xen 4.1.4 and compare it against Xen's original pre-copy approach. The evaluation results under various memory workloads show that our approach can significantly reduce total migration time and total pages transferred. © 2014 Springer-Verlag.