Performance Modelling
People
Practical techniques for estimating the performance
of computer and communication
systems forms a major strand of interest in our work.
Rob Pooley's work
My contribution has usually been in the application of simulation and in
tools supporting performance analysis. The Alvey SIMMER and ESPRIT II IMSE
projects (see below) represented an ambitious exploration of the possibilities
for computer supported performance analysis. In particular, we developed
the notion of software tools to support experimentation with performance
models in performance engineering, drawing on ideas from Zeigler. As a
continuation of this, I have worked with Dr Peter Thanisch at Edinburgh,
investigating the use of an object oriented database (ObjectStore) as a
means of supporting experimentation within a simulation environment. This
was funded within a SERC/EPSRC funded project, Simulation of Abstract Models
of Parallel Computation (ALAMO) (see below).
Communications
I am actively interested in modelling performance and behavioural properties
of communications networks. This currently includes work with Stephen Cusack,
a CASE student funded by BT, which is developing novel simulation techniques
to allow efficient simulation of ATM and other high bandwidth networks,
where the rarity of significant events and the frequency of transmission
events present insuperable problems for conventional discrete event simulation.
Peter King's work
I have worked mostly in more mathematical models of systems and network
performance. Theoretical models of Local area networks have been
developed, and also evaluated.
Previous MPhil students have investigated translation of LOTOS and Estelle
specifications in to Holzmann's Promella language to use its probabilistic
verifier.
More recently, with Hadi Larijani I have been
working on the effect of self similar traffic on queueing , and simple
techniques for estimating this.
Numerical solution techniques for Markov chains has been a major focus
of some unpublished work.
Work together
We have recently begun to examine how some of the integrated modelling
techniques developed in IMSE might be exploited in Computer Aided Software
Engineering tools, based around the emerging industry standard object oriented
design language, UML. We have published papers on this at the UK Performance
Engineering Workshop in July 1998 and in a forthcoming special issue of
IEE Proceedings on Software Engineering. Rob Pooley will be
presenting a tutorial on this work to the First International Workshop
on Software Performance (WOSP 98) in Santa Fe in October 1998. A grant
proposal for funding of this work is in preparation.