Transient performance evaluation of cloud computing applications and dynamic resource control in large-scale distributed systems

This paper discusses on non-stationary performance evaluation and dynamic modeling of cloud computing environments. In computer systems, dynamic effects results from the filling of buffers, event-handling delays, non-deterministic I/O response times, network latency, among other factors. While computer systems performance evaluation under stationary workloads have met the needs of many engineering problems, new challenges arise as the deployment of increasingly complex and large-scale distributed systems becomes commonplace. One key aspect of this discussion is that transient analysis models how the system reacts to changes in the workload and may reveal that the resources necessary to support a high steady-state workload may not be sufficient to handle a small, but sudden, workload change, even of intensity far smaller than that supported by the system´s stationary capacity. This article elaborates on these issues under a control-theoretical approach.