Modern supercomputing systems have witnessed a phenomenal growth in the recent history owing to the advent of multi-core architectures and high speed networks. However, the operational and maintenance costs of these systems have also grown rapidly. Several concepts such as Dynamic Voltage and Frequency Scaling (DVFS) and CPU Throttling have been proposed to conserve the power consumed by the compute nodes during idle periods. However, it is necessary to design software stacks in a power-aware manner to minimize the amount of power drawn by the system during the execution of applications. It is also critical to minimize the performance overheads associated with power-aware algorithms, as the benefits of saving power could be lost if the application runs for a longer time. Modern multi-core architectures such as the Intel "Nehalem" allow for DVFS and CPU throttling operations to be performed with little overheads. In this paper, we explore how these features can be leveraged to design algorithms to deliver fine-grained power savings during the communication phases of parallel applications. We also propose a theoretical model to analyze the power consumption characteristics of communication operations. We use microbenchmarks and application benchmarks such as NAS and CPMD to measure the performance of our proposed algorithms and to demonstrate the potential for saving power with 32 and 64 processes. We observe about 8% improvement in the overall energy consumed by these applications with little performance overheads.
Abstract:In Web Services designs classical optimization techniques are not applicable. A possible solution to guarantee critical requirements is the use of an autonomic architecture, able to autoconfigure and to auto-tune. This study presents MAWeS (MetaPL/HeSSE Autonomic Web Services), a framework whose aim is to support the development of self-optimizing predictive autonomic systems for Web service architectures. It adopts a simulation-based methodology, which allows to predict system performance in different status and load conditions. The predicted results are used for a feedforward control of the system, which self-tunes before the new conditions and the subsequent performance losses are actually observed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.