Performance evaluation of virtual machines in a service-oriented Grid testbed

In this paper we analyze the performance of execution of service workflows in virtual machines (VMs) used as resources in our service-oriented grid testbed (SGT).We chosen an application widely known by computer network researchers and developers to evaluate the testbed: the simulation of networks using the Network Simulator. We constructed workflows which execute several WiMAX network scenarios in parallel, and we executed them to evaluate the performance of virtual and physical machines in the grid. The experiments show that the adequate support to the parallelism can minimize the consequences of the overhead introduced by the VMs, allowing the simulation of several scenarios with execution time as low as one simulation alone would take. We conclude that it is important to have a VM-aware resource manager to completely explore the hardware and its VMs.