PowerPack: Energy Profiling and Analysis of High-Performance Systems and Applications

Energy efficiency is a major concern in modern high-performance computing system design. In the past few years, there has been mounting evidence that power usage limits system scale and computing density, and thus, ultimately system performance. However, despite the impact of power and energy on the computer systems community, few studies provide insight to where and how power is consumed on high-performance systems and applications. In previous work, we designed a framework called PowerPack that was the first tool to isolate the power consumption of devices including disks, memory, NICs, and processors in a high-performance cluster and correlate these measurements to application functions. In this work, we extend our framework to support systems with multicore, multiprocessor-based nodes, and then provide in-depth analyses of the energy consumption of parallel applications on clusters of these systems. These analyses include the impacts of chip multiprocessing on power and energy efficiency, and its interaction with application executions. In addition, we use PowerPack to study the power dynamics and energy efficiencies of dynamic voltage and frequency scaling (DVFS) techniques on clusters. Our experiments reveal conclusively how intelligent DVFS scheduling can enhance system energy efficiency while maintaining performance

MZnet : mail service for personal micro-computer systems

Traditional computer mail systems involve a co-resident User Agent (UA) and Mail Transfer System (MTS) on a time-shared host computer which may be connected to other hosts ina network, with new mail posted or delivered directly through co-resident mail-slot programs. To introduce personal micro-computers (PCs) into this environment requires modification of the traditional mail system architecture. To this end, the MZnet project uses a split-slot model, placing UA programs on the PCs while leaving MTA programs on a mail relay host which can provide authentication and buffering. The split-slot arrangement might be viewed as a new protocol level which operates somewhere between the currently defined MTS-MTS and UA-UA levels