Physical-level synthetic workload generation for load-balancing experiments

Synthetic workload generation uses artificial programs to mimic the resource-utilization patterns of real workloads. It is important for systematic evaluation of dynamic load-balancing strategies because load-balancing experiments require the measurement of task-completion times under realistic and reproducible workloads. The authors describe a generator that permits accurate replay of measured system-wide loads, thus providing an ideal setting for conducting load-balancing experiments. The generator is implemented inside the operating-system kernel and, therefore, has complete control over the local resources. It controls the useage levels of four key resources: CPU, memory, disk, and network. In order to reproduce accurately the behavior of the process population generating the measured load, the generator gives up a fraction of its resources in response to the arrival of new jobs, and reclaims these resources when the jobs terminate. The authors results show near-perfect reproduction of background load even in the presence of interfering foreground load