Introduction to Performance and Energy Efficiency Analysis

Annotation With the petering-out of Moore's law and the end of Dennard's scaling, the pace dictated on the performance increase of High Performance Computing (HPC) Systems among generations has led to power constrained architectures and even higher importance of the efficient utilization of the computation resources than before. In addition, power consumption represents a significant cost factor in the overall HPC system economy. For those reasons in recent years, researchers, supercomputing centres and major vendors have developed new tools and methodologies to measure and optimise the energy consumption of large scale high performance system installation. The well-established performance analysis tools are continuously adapted and enhanced to fit the specifics of the emerging architectures. These tools can provide an in-depth view on the application behaviour and support the decisions in the energy efficiency aspects. A robust performance analysis methodology can guide the developers through the various performance metrics to identify the fundamental causes of the performance inefficiencies of their application, which can be exploited by the energy-efficiency runtime systems. The course will offer an introduction to the fundamental concepts of performance, power consumption, and energy efficiency in HPC systems. Then it will focus on the performance analysis process and methodology developed during the POP project, followed by the mechanisms that today's computing elements and systems provide in terms of monitoring and control of power and energy dissipation. Finally, it will introduce and give hands-on sessions for a set of tools for performance analysis as well as reducing the energy consumption in HPC devices. The course is organised into two main sessions, driving the audience through the performance analysis workflow including the basics of the POP methodology, the physical and engineering principles underlying power consumption in supercomputing systems, up to the practical usage of state-of-the-art tools for monitoring and controlling the energy efficiency of parallel applications. The tools that will be covered are Extrae, Paraver, Basic Analysis (all BSC), MSR-SAFE (LLNL), MERIC (IT4I). Purpose of the course (benefits for the attendees) By the end of the course, participants will: learn how to use the presented performance tools and evaluate the performance metrics using the POP methodology have a good understanding of the principles underlying power consumption and energy dissipation in high performance computing nodes recognise trade-offs and the implications of changing the power consumption in scientific computing systems during the execution of scientific computing applications learn how to use these tools to optimise your codes for both performance and energy efficiency. Prerequisities The following background is expected from the participants: knowledge of C/C++, elementary notions of Linux/Unix knowledge of computing architecture experience in running HPC applications or systems basic knowledge of parallel programming OpenMP and/or MPI. Tools with graphical interface will be used during the course. Please, activate X-Window or install VNC (see e.g. IT4Innovations documentation) on your notebook before the training. Language Englis