A data‐centric framework for debugging highly parallel applications

Contemporary parallel debuggers allow users to control more than one processing thread while supporting the same examination and visualisation operations of that of sequential debuggers. This approach restricts the use of parallel debuggers when it comes to large scale scientific applications run across hundreds of thousands compute cores. First, manually observing the runtime data to detect error becomes impractical because the data is too big. Second, performing expensive but useful debugging operations becomes infeasible as the computational codes become more complex, involving larger data structures, and as the machines become larger. This study explores the idea of a data‐centric debugging approach, which could be used to make parallel debuggers more powerful. It discusses the use of ad hoc debug‐time assertions that allow a user to reason about the state of a parallel computation. These assertions support the verification and validation of program state at runtime as a whole rather than focusing on that of only a single process state. Furthermore, the debugger's performance can be improved by exploiting the underlying parallel platform because the available compute cores can execute parallel debugging functions, while a program is idling at a breakpoint. We demonstrate the system with several case studies and evaluate the performance of the tool on a 20 000 cores Cray XE6. Copyright © 2013 John Wiley & Sons, Ltd.     

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Book reviews

A Fourth Way? Privatization, Property and the Emergence of New Market Economies. Gregory S. Alexander & Grazyna Skapska (Eds). London, Routledge, 1994, xxiii + 336 pp., ISBN 0415906970 (HB), 0415906989 (PB)

From Public Housing to the Social Market. Rental Policy Strategies in Comparative Perspective. Jim Kemeny. London and New York, Routledge, 1995, 194 pp., £40.00

European Housing Finance. Single Market or Mosaic?. Will Bartlett & Glen Bramley (Eds). Oxford, The Alden Press, School for Advanced Urban Studies (SAUS) publication 12 (Bristol) 1994, 282 pp., £19.95, paperback, ISBN 1 873575 63 7

Housing, Financial Markets and the Wider Economy. David Miles. Chichester, John Wiley & Sons, 1994, 228 pp., £35.00

Women in the Housing Service. Marion Brion. London, Routledge, 1994, ISBN 0 415 08094 £45.00 Hardback

Slippery Customers: Estate Agents, The Public and Regulation. Michael Clarke, David Smith & Michael McConville. London, Blackstone Press, 1994, 295 pp., £19.95     

An evaluation tool for design quality: PFI sheltered housing

The complex procurement process entailed by the private finance initiative (PFI) means that clients need new capacities to manage their relationships with bidders and to assess project proposals if the desired level of design quality is to be achieved. To assist local authorities in their client role, a new Architectural Design Quality Evaluation Tool was developed. The aim was to improve the quality of design in residential sheltered housing, procured through the PFI. The tool was developed for and applied to a programme that will see the replacement of a local authority's entire sheltered housing stock. The tool has two functions: (1) to inform the client's assessment process and assist with the selection of the preferred bidding consortium through a series of stages in the PFI process; and (2) to improve the quality of all the submitted designs through an iterative process. Although several existing mechanisms are available for evaluating the performance attributes of buildings, few also tackle the less tangible amenity attributes, which are vital to the feeling of home. The new tool emphasizes the amenity attributes without neglecting performance.