Tesis doctoral de Unai Lopez Novoa
The high performance computing landscape is shifting from assemblies of homogeneous nodes towards heterogeneous systems, in which nodes consist of a combination of traditional out-of-order execution cores and accelerator devices. Accelerators provide greater theoretical performance compared to traditional multi-core cpus, but exploiting their computing power remains as a challenging task.This dissertation discusses the issues that arise when trying to efficiently use general purpose accelerators. As a contribution to aid in this task, we present a thorough survey of performance modeling techniques and tools for general purpose coprocessors. Then we use as case study the statistical technique kernel density estimation (kde). Kde is a memory bound application that poses several challenges for its adaptation to the accelerator-based model. We present a novel algorithm for the computation of kde that reduces considerably its computational complexity, called s-kde. Furthermore, we have carried out two parallel implementations of s-kde, one for multi and many-core processors, and another one for accelerators. The latter has been implemented in opencl in order to make it portable across a wide range of devices. We have evaluated the performance of each implementation of s-kde in a variety of architectures, trying to highlight the bottlenecks and the limits that the code reaches in each device. Finally, we present an application of our s-kde algorithm in the field of climatology: a novel methodology for the evaluation of environmental models.
Datos académicos de la tesis doctoral «Contributions to the efficient use of general purpose coprocessors: kernel density estimation as case study«
- Título de la tesis: Contributions to the efficient use of general purpose coprocessors: kernel density estimation as case study
- Autor: Unai Lopez Novoa
- Universidad: País vasco/euskal herriko unibertsitatea
- Fecha de lectura de la tesis: 19/06/2015
Dirección y tribunal
- Director de la tesis
- Alexander Mendiburu Alberro
- Tribunal
- Presidente del tribunal: clemente Rodriguez lafuente
- José angel Gregorio monasterio (vocal)
- diego Lopez de ipiña gonzalez de artaza (vocal)
- leonel augusto Pires seabara de sousa (vocal)