Alistair N. Dunlop

A distributed scientific data archive using the Web, XML and SQL/MED

We have developed a web-based architecture and user interface for fast storage, searching and retrieval of large, distributed, files resulting from scientific simulations. We demonstrate that the new DATALINK type defined in the draft SQL Management of External Data Standard can help to overcome problems associated with limited bandwidth when trying to archive large files using the web. We also show that separating the user interface specification from the user interface processing can provide a number of advantages. We provide a tool to generate automatically a default user interface specification, in the form of an XML document, for a given database. This facilitates deployment of our system by users with little web or database development experience. The XML document can be customised to change the appearance of the interface.

Realistic parallel performance estimation

Abstract This paper presents an account of two tools which enable realistic parallel performance estimates to be obtained in reasonable time. The first tool, PERFORM (performance estimator for RISC microprocessors), is a general purpose package for sequential program performance estimation on modern RISC microprocessor nodes with complex memory hierarchies. The novelty of the tool is that we have chosen an intermediate level of abstraction between simple statement counting and full simulation of the node architecture. The second tool, LEBEP, generates synthetic parallel programs from a simple communication specification. In particular, it can generate communication operations that incurs typical communication overhead, including data movements across different levels in the memory hierarchy.

Portable Parallel Programming Environment - The ESPRIT PPPE Project

Keywords : Parallel performance monitoring, debugging, software engineering, integrated toolset.

A toolkit for optimising parallel performance

Three interacting tools to assist distributed memory programmers in developing, optimising and understanding application performance have been developed. These tools perform automatic code generation from an initial workload specification, performance prediction using memory hierarchy simulation, and performance visualisation for distributed memory message passing applications. Their combination facilitates extensive performance tuning from initial workload specification through to completed message passing program codes.