Evaluation of Multiprocessor Interconnection Networks:
Project Overview

EMIN is a UK EPSRC funded project to evaluate multiprocessor interconnection networks, carried out in the Department of Computer Science at the University of Edinburgh. It is a component of an ongoing long-term strategy to undertake quantitative evaluation of computer architectures.

The EMIN project involves the evaluation of a variety of multiprocessor interconnection networks. A simulation testbed containing processor models, which can generate network activity corresponding to that found in standard benchmarks used in the evaluation of real parallel systems, has been set up. Each of the different networks of interest can be instantiated in the testbed, and its performance observed.

The Problem

Designing multiprocessor systems is complicated because of the varied interactions between parallel software and hardware. Evaluating the impact of design decisions on overall performance is difficult. The EMIN project seeks to address these issues by developing a simulation testbed for designing and analysing multiprocessor interconnection network performance.

The Solution

Rather than apply a single technique to the problem, a suite of design techniques has been used. The simplest (and often overlooked) technique is spreadsheet analysis. This enables quick broad brush comparisons of networks. Microbenchmarks are useful both for characterising network performance and for providing data which is relevant to software. Discrete event simulation is an extremely powerful technique for evaluating performance of complex interacting hardware/software systems; we have developed DES techniques based on both Java ( the Simjava library) and C++ and threads (the HASE++ library). This document describes techniques for Interactive modelling of interconnection network design based on Web technology. The issue of technical documentation is interwoven with that of simulation, allowing for active diagrams to explain complex models.

Visualisation

For a design tool to be effective, the turnaround time must be small and the results must be visible and understandable. Visualisation of simulation results is therefore crucial. The following is a screen shot of a visualisation tool developed for viewing simulation results as a timing diagram.

Simjava takes this one step further, and allows live simulations to be included into documentation.

The Results


Fred Howell
Computer Systems Group
Department of Computer Science
The University of Edinburgh
King's Buildings
Edinburgh EH9 3JZ

Last modified: Tue May 26 1997