Relative debugging and its application to the development of large numerical models

The Removal of Numerical Drift from Scientific Models

“…However, this could be further improved by expanding the experimentation to also include multiprocessor builds. One aim of future work on the project is to investigate the combination of aspects of this technique and the relative debugging techniques developed by Abramson et al [2] to analyse runs made on multiprocessor systems.…”

“…The Guard system was developed as a means of implementing automated relative debugging [2]. The project was driven by the fluid nature of software development for scientific modelling in which a community contributes towards the on-going development of the model.…”

“…In looking for possible bugs, the user declares assertions to specify which data structures to monitor and where in the code they are to be compared (Abramson et al 1995). The point in the code where a comparison is made that result in significant differences is unlikely to be the point where the differences are being generated.…”

“…This is achieved through the comparison of values between a reference program and a development program (Figure 1). Abramson et al [2] describe the successful application of a relative debugging technique for a program running in a sequential and a parallel environment. Their technique requires the user to specify specific data structures to be compared during the different program runs.…”

Backtracking and re-execution in the automatic debugging of parallelized programs

“…• fully interactive parallelization too s. where user inputs steer the parallelization process [3 [ 1].…”