Performance and Power Analysis of HPC Workloads on Heterogenous Multi-Node Clusters

Performance analysis tools allow application developers to identify and characterize the inefficiencies that cause performance degradation in their codes, allowing for application optimizations. Due to the increasing interest in the High Performance Computing (HPC) community towards energy-efficiency issues, it is of paramount importance to be able to correlate performance and power figures within the same profiling and analysis tools. For this reason, we present a performance and energy-efficiency study aimed at demonstrating how a single tool can be used to collect most of the relevant metrics. In particular, we show how the same analysis techniques can be applicable on different architectures, analyzing the same HPC application on a high-end and a low-power cluster. The former cluster embeds Intel Haswell CPUs and NVIDIA K80 GPUs, while the latter is made up of NVIDIA Jetson TX1 boards, each hosting an Arm Cortex-A57 CPU and an NVIDIA Tegra X1 Maxwell GPU.The research leading to these results has received funding from the European Community’s Seventh Framework Programme [FP7/2007-2013] and Horizon 2020 under the Mont-Blanc projects [17], grant agreements n. 288777, 610402 and 671697. E.C. was partially founded by “Contributo 5 per mille assegnato all’Università degli Studi di Ferrara-dichiarazione dei redditi dell’anno 2014”. We thank the University of Ferrara and INFN Ferrara for the access to the COKA Cluster. We warmly thank the BSC tools group, supporting us for the smooth integration and test of our setup within Extrae and Paraver.Peer ReviewedPostprint (published version

Overcoming Language Dichotomies: Toward Effective Program Comprehension for Mobile App Development

Mobile devices and platforms have become an established target for modern software developers due to performant hardware and a large and growing user base numbering in the billions. Despite their popularity, the software development process for mobile apps comes with a set of unique, domain-specific challenges rooted in program comprehension. Many of these challenges stem from developer difficulties in reasoning about different representations of a program, a phenomenon we define as a "language dichotomy". In this paper, we reflect upon the various language dichotomies that contribute to open problems in program comprehension and development for mobile apps. Furthermore, to help guide the research community towards effective solutions for these problems, we provide a roadmap of directions for future work.Comment: Invited Keynote Paper for the 26th IEEE/ACM International Conference on Program Comprehension (ICPC'18

Synergy: An Energy Monitoring and Visualization System

The key to becoming a more sustainable society is first learning to take responsibility for the role we play in energy consumption. Real-time energy usage gives energy consumers a sense of responsibility over what they can do to accomplish a much larger goal for the planet, and practically speaking, what they can do to lower the cost to their wallets. Synergy is an energy monitoring and visualization system that enables users to gather information about the energy consumption in a building – small or large – and display that data for the user in real-time. The gathered energy usage data is processed on the edge before being stored in the cloud. The two main benefits of edge processing are issuing electricity hazard warnings immediately and preserving user privacy. In addition to being a scalable solution that intended for use in individual households, commercial offices and city power grids, Synergy is open-source so that it can be implemented more widely. This paper contains a system overview as well as initial finding based on the data collected by Synergy before assessing the impact the system can have on society

ElecTrack - Mobile Electricity Usage Tracking and Visualizing

The main objective of this project is to develop an electricity usage tracking application for all mobile Android platform to effectively track their electricity usage over time and hopefully will also help to raise awareness towards the conservation of energy and preserving the quality of the environment. This application features the ability of monitoring the electricity usage, by using the inputs that the users had entered to calculate the total electricity consumption based on the unit Watts (W). Another important feature of this application is the functionality to visualize the overall electricity consumption in various graphical forms as an approach for the users to review the distribution of their electricity consumption. Researches and studies were done on several articles, research papers and other sources of information related to the subject. A number of previously conducted experimental studies were also used to support the study and development of this project. These sources of references were critically analyzed through an extensive research methodology whereby every key aspects of the information were extracted and used for literature review. The development of this application will be conducted in Java programming language, by utilizing Android Software Development Kit (SDK) to support the development of this application. The methodology used for the development of this application is Rapid Application Development (RAD) – Prototyping method. The justification for the selection of the above methodology is because of the time constraint for this project. Therefore, this method is the most suitable since it involves fast and interactive development processes of the prototype which will suit this project the best. The prototypes are tested continuously for feedbacks until the final prototype is ready to be released. The final release of the prototype is also tested with potential users for usability and acceptance testing. The final prototype is able to provide dynamic feedback for households’ electricity consumption and by providing tailored information regarding electricity consumption pattern, awareness towards energy conservation can be raised

ENTRA:Whole-systems energy transparency

Promoting energy efficiency to a first class system design goal is an important research challenge. Although more energy-efficient hardware can be designed, it is software that controls the hardware; for a given system the potential for energy savings is likely to be much greater at the higher levels of abstraction in the system stack. Thus the greatest savings are expected from energy-aware software development, which is the vision of the EU ENTRA project. This article presents the concept of energy transparency as a foundation for energy-aware software development. We show how energy modelling of hardware is combined with static analysis to allow the programmer to understand the energy consumption of a program without executing it, thus enabling exploration of the design space taking energy into consideration. The paper concludes by summarising the current and future challenges identified in the ENTRA project.Comment: Revised preprint submitted to MICPRO on 27 May 2016, 23 pages, 3 figure

METHOD FOR VISUALISING ENERGY SOURCES POWERING BLOCKCHAIN TRANSACTIONS AND APPARATUS THEREOF

The present disclosure relates to a technique for providing visualization of energy sources powering the blockchain transactions. The technique involves determining the energy consumption pattern of each participating node during a transaction. The health of a card associated with a user is displayed by comparing the energy consumption associated with the blockchain transactions performed by the user with a pre-determined threshold. In one embodiment, the health of the card is determined based on the energy consumption report and carbon footprints associated with the transactions. Further, the technique further comprises triggering car linked offers (CLOs) for the user to offset the non-renewable energy consumed. The visualization of energy profile triggers green financial decisions at user end and it additionally offers loyalty points to users for offsetting their unsustainable energy consumption and thus gamifies the whole experience of attaining a greener planet

Performance analysis methods for understanding scaling bottlenecks in multi-threaded applications

In dit proefschrift stellen we drie nieuwe methodes voor om de prestatie van meerdradige programma's te analyseren. Onze eerste methode, criticality stacks, is bruikbaar voor het analyseren van onevenwicht tussen draden. Om deze stacks te construeren stellen we een nieuwe criticaliteitsmetriek voor, die de uitvoeringstijd van een applicatie opsplitst in een deel voor iedere draad. Hoe groter dit deel is voor een draad, hoe kritischer deze draad is voor de applicatie. De tweede methode, bottle graphs, stelt iedere draad van een meerdradig programma voor als een rechthoek in een grafiek. De hoogte van de rechthoek wordt berekend door middel van onze criticaliteitsmetriek, en de breedte stelt het parallellisme van een draad voor. Rechthoeken die bovenaan in de grafiek zitten, als het ware in de hals van de fles, hebben een beperkt parallellisme, waardoor we ze beschouwen als “bottlenecks” voor de applicatie. Onze derde methode, speedup stacks, toont de bereikte speedup van een applicatie en de verschillende componenten die speedup beperken in een gestapelde grafiek. De intuïtie achter dit concept is dat door het reduceren van de invloed van een bepaalde component, de speedup van een applicatie proportioneel toeneemt met de grootte van die component in de stapel