Performance evaluation of Web server workloads in Xen-based virtualized computer system: analytical modeling and experimental validation

摘要

Recent developments in the field of virtualization technologies have led to renewed interest in performancernevaluation of these systems. Nowadays, maturity of virtualization technology has made a fussrnof provisioning IT services to maximize profits, scalability and QoS. This pioneer solution facilitatesrndeployment of datacenter applications and grid and Cloud computing services; however, there arernchallenges. It is necessary to investigate a trade-off among overall system performance and revenuernand to ensure service-level agreement of submitted workloads. Although a growing body of literaturernhas investigated virtualization overhead and virtual machines interference, there is still lack of accuraternperformance evaluation of virtualized systems. In this paper, we present in-depth performancernmeasurements to evaluate a Xen-based virtualized Web server. Regarding this experimental study;rnwe support our approach by queuing network modeling. Based on these quantitative and qualitativernanalyses, we present the results that are important for performance evaluation of consolidatedrnworkloads on Xen hypervisor. First, demands of both CPU intensive and disk intensive workloadsrnon CPU and disk are independent from the submitted rate to unprivileged domain when dedicatedrncore(s) are pinned to virtual machines. Second, request response time not only depends on processingrntime at unprivileged domain but also pertains to amount of flipped pages at Domain 0. Finally, resultsrnshow that the proposed modeling methodology performs well to predict the QoS parameters in bothrnpara-virtualized and hardware virtual machine modes by knowing the request content size.