From Social Simulation to Integrative System Design

As the recent financial crisis showed, today there is a strong need to gain "ecological perspective" of all relevant interactions in socio-economic-techno-environmental systems. For this, we suggested to set-up a network of Centers for integrative systems design, which shall be able to run all potentially relevant scenarios, identify causality chains, explore feedback and cascading effects for a number of model variants, and determine the reliability of their implications (given the validity of the underlying models). They will be able to detect possible negative side effect of policy decisions, before they occur. The Centers belonging to this network of Integrative Systems Design Centers would be focused on a particular field, but they would be part of an attempt to eventually cover all relevant areas of society and economy and integrate them within a "Living Earth Simulator". The results of all research activities of such Centers would be turned into informative input for political Decision Arenas. For example, Crisis Observatories (for financial instabilities, shortages of resources, environmental change, conflict, spreading of diseases, etc.) would be connected with such Decision Arenas for the purpose of visualization, in order to make complex interdependencies understandable to scientists, decision-makers, and the general public.Comment: 34 pages, Visioneer White Paper, see http://www.visioneer.ethz.c

The 30th Anniversary of the Supercomputing Conference: Bringing the Future Closer - Supercomputing History and the Immortality of Now

A panel of experts discusses historical reflections on the past 30 years of the Supercomputing (SC) conference, its leading role for the professional community and some exciting future challenges

From social simulation to integrative system design

Abstract.: The purpose of this White Paper of the EU Support Action "Visioneer” (see www.visioneer.ethz.ch) is to address the following goals: 1.Develop strategies to build up social simulation capacities.2.Suggest ways to build up an "artificial societies” community that aims at simulating real and alternative societies by means of supercomputers, grid or cloud computing.3.Derive proposals to establish centers for integrative systems desig

The Silent Arms Race: The Role of the Supercomputer During the Cold War, 1947-1963

One of the central features of the Cold War is the Arms Race. The United States and the Union of Soviet Socialist republics vied for supremacy over the globe for a fifty-year period in which there were several arms races; atomic weapons, thermonuclear weapons and various kinds of conventional weapons. However, there is another arms race that goes unsung during this period of history and that is in the area of supercomputing. The other types of arms races are taken for granted by historians and others, but the technological competition between the superpowers would have been impossible without the historically silent arms race in the area of supercomputers. The construction of missiles, jets as well as the testing of nuclear weapons had serious implications for international relations. Often perception is more important than fact. Perceived power maintained a deterrent effect on the two superpowers. If one superpower suspected that they, in fact, had an advantage over the other then the balance of power would be upset and more aggressive measures might have been taken in various fronts of the conflict, perhaps leading to war. Due to this, it was necessary to maintain a balance of power not only in weapons but in supercomputing as well. Considering the role that the computers played, it is time for closer historical scrutiny

Performance impact of the interconnection network on MareNostrum applications

Interconnection networks are one of the fundamental components of a supercomputing facility, and one of the most expensive parts. They represent one of the main differences between two supercomputers built from the same processor, and have a significant impact on how the applications should be developed. However, very little is known about how those expensive interconnection networks are used by the real applications running on supercomputing facilities. Furthermore, in the near future, chip multiprocessors offering near supercomputing capabilities, with 64 to 256 processor per chip, will be readily available. Onchip interconnection networks offer the possibility of new designs with lower latencies and much higher bandwidths. In this paper we present an analysis of the impact of the interconnection network for some of the most representative applications running on MareNostrum, at the Barcelona Supercomputing Center. We have collected traces of real runs of the applications, and verified that our performance model (Dimemas) accurately predicts the real machine performance. Then, we present hypothetical situations where we change the network’s latency, bandwidth, number of simultaneous connections, and CPU speed in order to quantify their importance on the final application performance in the context of future on-chip interconnenctions. Our results show that the CPU speed proves more important than the interconnection network, and that among the network’s parameters, interconnection bandwidth is far more important than latency (with a very low impact), or the connectivity (only relevant for low connection bandwidth).Peer ReviewedPostprint (author's final draft