05501 Abstracts Collection -- Automatic Performance Analysis

From 12.12.05 to 16.12.05, the Dagstuhl Seminar 05501 ``Automatic Performance Analysis\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

09131 Abstracts Collection -- Service Level Agreements in Grids

From 22.03. to 27.03.09, the Dagstuhl Seminar 09131 ``Service Level Agreements in Grids \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

ESID: A Visual Analytics Tool to Epidemiological Emergencies

Visual analysis tools can help illustrate the spread of infectious diseases and enable informed decisions on epidemiology and public health issues. To create visualisation tools that are intuitive, easy to use, and effective in communicating information, continued research and development focusing on user-centric and methodological design models is extremely important. As a contribution to this topic, this paper presents the design and development of the visual analytics application ESID (Epidemiological Scenarios for Infectious Diseases). The goal of ESID is to provide a platform for rapid assessment of the most effective interventions for infectious disease control. ESID provides spatial-temporal analysis, forecasting, comparison of simulations, interactive filters, and accessibility options. In its current form, it shows the simulations of a hybrid graph-equation-based model as introduced in for infection control. The model can be stratified for different age groups and takes into account the properties of the infectious disease as well as human mobility and contact behaviour.Comment: 6 pages, 5 images and 1 table, Eurovis workshop on visual analytics (EuroVA) 202

FSSteering: A Distributed Framework for Computational Steering in a Script-based CFD Simulation Environment

In order to get insight into interesting flow phenomena, the traditional work-flow of computational fluid dynamics (CFD) consists of setting up and computing the flow field followed by a consecutive post-processing analysis. Only after this analysis one can identify parameters that may have been set wrongly in a configuration stage. Once these parameters are corrected, another time-consuming loop has to be started. To identify inadequate parameter settings already during the simulation run, online monitoring concepts were introduced. Combined with computational steering methods, parameter values can additionally be adjusted which eventually reduces the number of required iterations to yield satisfactory results. At the German Aerospace Center, a comprehensive framework called FlowSimulator has been developed to offer a generic Python-based interface for the management of CFD simulations. It can easily be enhanced by add-ons. One of these extensions is FSSteering which is described in this paper in more detail. As a computational steering environment, FSSteering provides functionalities essential for interactive visualization and explorative analysis. Besides existing computational steering environments and frameworks, a user-centred and domain-specific view is proposed. Existing functionality can be reused without rewriting simulation code to enable for effective steering in CFD. To be more efficient, components of the architecture are distributed across different resources. Whereas the CFD simulation typically runs on a parallel supercomputer, the visualization is carried out on a high-performance virtual reality system which allows interactive data exploration. The post-processing in between can be performed on the supercomputer or on a separate parallelization cluster. But it is also possible to switch between different existing post-processing toolkits. This is just possible because of the very flexible configuration management of the distributed steering framework. We will demonstrate the steering capabilities and the system flexibility by two current research examples. An outlook for future steps concludes this paper

Dark Silicon: From Embedded to HPC Systems (Dagstuhl Seminar 16052)

Semiconductor industry is hitting the utilization wall and puts focus on parallel and heterogeneous many-core architectures. While continuous technological scaling enables the high integration of 100s-1000s of cores and, thus, enormous processing capabilities, the resulting power consumption per area (the power density) increases in an unsustainable way. With this density, the problem of Dark Silicon will become prevalent in future technology nodes: It will be infeasible to operate all on-chip components at full performance at the same time due to the thermal constraints (peak temperature, spatial and temporal thermal gradients etc.). However, this is not only an emerging threat for SoC and MPSoC designers, HPC faces a similar problem as well: The power supplied by the energy companies as well as the cooling capacity does not allow to run the entire machine at highest performance anymore. The goal of Dagstuhl Seminar 16052 "Dark Silicon: From Embedded to HPC Systems" was to increase the awareness of the research communities of those similarities and to work and explore common solutions based on more flexible thermal/power/resource management techniques both for runtime, design time as well as hybrid solutions

Concurrent File Operations in a High Performance FORTRAN

Distributed memory multiprocessor systems can provide the computing power necessary for large-scale scientific applications. A critical performance issue for a number of these applications is the efficient transfer of data to secondary storage. Recently several research groups have proposed FORTRAN language extensions for exploiting the data parallelism of such scientific codes on distributed memory architectures. However, few of these high performance FORTRANs provide appropriate constructs for controlling the use of the parallel I/O capabilities of modern multiprocessing machines. In this paper, we propose constructs to specify I/O operations for distributed data structures in the context of Vienna Fortran. These operations can be used by the programmer to provide information which can help the compiler and runtime environment make the most efficient use of the I/O subsystem. 1 Introduction Distributed memory multiprocessors (DMMPs), such as Intel's Paragon and Thinking Machines' CM..

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This report documents the program and the outcomes of Dagstuhl Seminar 13401 “Automatic Application Tuning for HPC Architectures”. This workshop featured a series of talks and four breakout sessions on hot topics in the are of autotuning. The field of autotuning for HPC applications is of growing interest and many research groups around the world are currently involved. However, the field is still rapidly evolving with many different approaching being taken to autotuning. This workshop provided an opportunity to discuss these many approaches, and help to unify the terminology used by different groups

SUPERB Support for Irregular Scientific Computations

Runtime support for parallelization of scientific programs is needed when some information important for decisions in this process cannot be accurately derived at compile time. This paper describes a project which integrates runtime parallelization with advanced compile-time parallelization techniques of SUPERB. Besides the description of implementation techniques, language constructs are proposed, providing means for the specification of irregular computations. SUPERB is an interactive SIMD/MIMD parallelizing system for the SUPRENUM, iPSC/860 and GENESIS-P machines. The implementation of the runtime parallelization is based on the Parti procedures developed at ICASE NASA. 1 Introduction SUPERB (SUprenum ParallelizER Bonn) ([3, 17]) is a semi-automatic parallelization tool for distributed memory multiprocessors, e.g. SUPRENUM, iPSC/860 and GENESIS-P. It is a source-to-source transformation system which translates Fortran 77 programs into parallel programs written in the Fortran diale..