high performance computing on graphics processing units: hgpu.org

In the last decades cosmological N-body dark matter simulations have enabled ab initio studies of the formation of structure in the Universe. Gravity amplified small density fluctuations generated shortly after the Big Bang, leading to the formation of galaxies in the cosmic web. These calculations have led to a growing demand for methods to analyze […]

We present the GPU based acceleration of two well known nonlinear optimization routines: Levenberg-Marquardt (LM) and Limited Memory Broyden-Fletcher-Goldfarb-Shanno (LBFGS) in radio interferometric calibration. Radio interferometric calibration is a heavily compute intensive operation where the same nonlinear optimization problem has to be solved over many time intervals, with different data. We achieve a speedup of […]

Software security and reliability have become increasingly important in the modern world. An effective approach to enforcing software security and reliability is to monitor a program’s execution at run time. However, instrumentation-based implementation of a dynamic program monitor on single-core systems suffers significant performance overhead. As multi-core architecture becomes more mainstream, implementing efficient dynamic program […]

Clustering algorithms have wide applications in Computer Vision, Data mining, Data Visualization, etc. Clustering is an important step for indexing and searching of documents, images, video, etc. Clustering large numbers of high-dimensional vectors is very computation intensive. CPUs are unable to handle such load and consume sometimes days and even weeks to cluster large data. […]

While high-efficiency machines are increasingly embracing heterogeneous architectures and massive multithreading, contemporary mainstream programming languages reflect a mental model in which processing elements are homogeneous, concurrency is limited, and memory is a flat undifferentiated pool of storage. Moreover, the current state of the art in programming heterogeneous machines tends towards using separate programming models, such […]

This thesis reviews if OpenCL is a suitable and cost effective platform for algorithm development in health care systems. Aspects such as maintainability, performance, portability and integration with high-level languages (in this case Python) are analyzed. The review is done by implementing one part of a dose calculation algorithm that is complex enough to provide […]

Without doubt, the fast Fourier transform (FFT) belongs to the algorithms with large impact on science and engineering. By appropriate approximations, this scheme has been generalized for arbitrary spatial sampling points. This so called nonequispaced FFT is the core of the sequential NFFT3 library and we discuss its computational costs in detail. On the other […]

Using passwords to verify a user’s identity is the most widely deployed method for electronic authentication. When system administrators need to recover lost passwords or test accounts for easily guessable passwords, it can require millions of hash function and string comparison operations. These operations can be computationally expensive but are easily parallelizable because each password […]

Current trends in computing and system architecture point towards a need for accelerators such as GPUs to have inherent communication capabilities. We review previous and current software libraries that provide pseudo-communication abilities through direct message passing. We show how these libraries are beneficial to the HPC community, but are not forward-thinking enough. We give motivation […]

Scalable systems and services for preserving digital content became important technologies with increasing volumes of digitized data. This paper presents a new Braille converter service that is a sample implementation of scalable service for preserving digital content. The converter service facilitates complex conversion problems regarding Braille code. Braille code is a method which allows visually […]

In this work we consider Runge-Kutta discontinuous Galerkin methods (RKDG) for the solution of hyperbolic equations enabling high order discretization in space and time. We aim at an efficient implementation of DG for Euler equations on GPUs. A mesh curvature approach is presented for the proper resolution of the domain boundary. This approach is based […]

There is no one size fits all solution when it comes to CT reconstruction. Many different CT reconstruction algorithms and implementations have been devised in an attempt to solve the problem of producing an image under a specific set of constraints. One optimal CT reconstruction implementation can look very different from another optimal implementation; depending […]