Backfilling under Two-tier Virtual Machines

The cloud computing paradigm attracts increasing amount of efforts to move high performance parallel applications to run in remote data centres. How to balance the performance requirements of parallel applications and the data centre utilization is essential to the move. Existing parallel scheduling mechanisms normally do not consider workload consolidation for improving server utilization. In this paper, we propose a two-tier architecture to organize virtual machines for workload consolidation. The two-tier virtual machines have different CPU priorities. We give a parallel job scheduling algorithm called Two EASY, which extends EASY algorithm, to take care of the job responsiveness in such an architecture. Our extensive experiments show that TwoEASY significantly outperforms the commonly used EASY algorithm in a datacentre setting. The method is practical and effective for consolidating parallel workload in datacentres.