A domain-specific high-level programming model

International audienceNowadays, computing hardware continues to move toward more parallelism and more heterogeneity, to obtain more computing power. From personal computers to supercomputers, we can find several levels of parallelism expressed by the interconnections of multi-core and many-core accelerators. On the other hand, computing software needs to adapt to this trend, and programmers can use parallel programming models (PPM) to fulfil this difficult task. There are different PPMs available that are based on tasks, directives, or low level languages or library. These offer higher or lower abstraction levels from the architecture by handling their own syntax. However, to offer an efficient PPM with a greater (additional) high-levelabstraction level while saving on performance, one idea is to restrict this to a specific domain and to adapt it to a family of applications. In the present study, we propose a high-level PPM specific to digital signal processing applications. It is based on data-flow graph models of computation, and a dynamic runtime model of execution (StarPU). We show how the user can easily express this digital signal processing application, and can take advantage of task, data and graph parallelism in the implementation, to enhance the performances of targeted heterogeneous clusters composed of CPUs and different accelerators (e.g., GPU, Xeon Phi

The developer's guide to debugging

New Yorkxix, 224 p.; 24 cm

Fast Kriging-based Error Evaluation for Approximate Computing Systems

International audienceApproximate computing techniques trade-off the performance of an application for its accuracy. The challenge when implementing approximate computing in an application is to efficiently evaluate the quality at the output of the application to optimize the noise budgeting of the different approximation sources. It is commonly achieved with an optimization algorithm to minimize the implementation cost of the application subject to a quality constraint. During the optimization process, numerous approximation configurations are tested, and the quality at the output of the application is measured for each configuration with simulations. The optimization process is a time-consuming task. We propose a new method for infering the accuracy or quality metric at the output of an application using kriging, a geostatistical method