Job Completion Time on a Virtualized Server Subject to Software Aging and Rejuvenation

Virtual machine monitor (VMM) rejuvenation is a proactive recovery method against failures caused by software aging in VMM. Since the job running on a hosted virtual machine (VM) is interrupted at VMM rejuvenation, the preemption type of VMM rejuvenation is important for the performance of job execution. In preemptive repeat (prt), the interrupted job needs to restart after recovery. In preemptive resume (prs), the job can resume the execution from the interrupted point. In this paper, we analyze the completion time of a job running on a virtualized server subject to software aging and rejuvenation in prt case or prs case. The theory developed in [1] is used to obtain the Laplace-Stieltjes transform (LST) of job completion time for the server modeled as a semi-Markov process. Numerical inversion of the obtained LST shows that VMM rejuvenation with prs job interruption improves the performance of job execution, while the rejuvenation with prt job interruption may degrade or improve its performance depending on the severity of performance degradation caused by software aging.