Optimizing live migration of virtual machines across wide area networks using integrated replication and scheduling

Abstract

Migrating virtual machines (VM) at run time within acceptable time limits is significantly challenging due to large size of the virtual disk files. In this paper, we propose our framework called cloudspider to overcome this challenge by combining replication and scheduling of VM images into a common framework. In particular, we replicate VM images apriori onto a few chosen cloud sites and select one of the replicas of the VM image to be the primary copy. Based on dynamically changing cost parameters at these cloud sites, the scheduler can appropriately select a different replica of a VM image to be the primary copy. The updates at the primary copy are incrementally propagated to the remaining copies. In order to bring down the cost of storage requirement due to the additional replicas our work proposes the use of deduplication techniques. In this paper we address the question of replica placement of VM images when disparate VM images have varying degrees of commonality and latency requirements. The replication algorithm has been implemented and tested using an open-source cloud simulator called CloudSim and the initial results are quite promising.

Challenges and New Solutions for Live Migration of Virtual Machines in Cloud Computing Environments

“…Different migration mechanisms exploit different types of similarities to facilitate VM storage data migration according to migration conditions. Bose et al [17,16] propose to decrease migration time at the expense of storage space. They keep several replicas of a VM image at different cloud data centers, and choose one replica as the primary copy.…”

“…As shown in Figure 6.8, the migration initialization mechanism for JDM significantly reduces the service degradation time. Due to a careful orchestration of migration process, the service degradation time only contains the downtime of memory data migration which has been optimized to the millisecond level by existing technologies [29,119,17,81]. However, both M-enter and M-leave have a big service degradation time because of a remote connection between a UE and its VM, even though M-enter experiences a shorter storage data migration than JDM for VM2.…”