Abstract-In bioinformatics, alignments are commonly performed in genome and protein sequence analysis for gene identification and evolutionary similarities. There are several approaches for such analysis, each varying in accuracy and computational complexity. Smith-Waterman (SW) is by far the best algorithm for its accuracy in similarity scoring. However, execution time of this algorithm on general purpose processor based systems makes it impractical for use by life scientists. In this paper we take Smith-Waterman as a case study to explore the architectural features of Graphics Processing Units (GPUs) and evaluate the challenges the hardware architecture poses, as well as the software modifications needed to map the program architecture on to the GPU. We achieve a 23x speedup against the serial version of the SW algorithm. We further study the effect of memory organization and the instruction set architecture on GPU performance. For that purpose we analyze another implementation on an Intel Quad Core processor that makes use of Intel's SIMD based SSE2 architecture. We show that if reading blocks of 16 words at a time instead of 4 is allowed, and if 64KB of shared memory as opposed to 16KB is available to the programmer, GPU performance enhances significantly making it comparable to the SIMD based implementation. We quantify these observations to illustrate the need for studies on extending the instruction set and memory organization for the GPU.

Program development environments have enabled graphics processing units (GPUs) to become an attractive high performance computing platform for the scientific community. A commonly posed problem in computational biology is protein database searching for functional similarities. The most accurate algorithm for sequence alignments is Smith-Waterman (SW). However, due to its computational complexity and rapidly increasing database sizes, the process becomes more and more time consuming making cluster based systems more desirable. Therefore, scalable and highly parallel methods are necessary to make SW a viable solution for life science researchers. In this paper we evaluate how SW fits onto the target GPU architecture by exploring ways to map the program architecture on the processor architecture. We develop new techniques to reduce the memory footprint of the application while exploiting the memory hierarchy of the GPU. With this implementation, GSW, we overcome the on chip memory size constraint, achieving 23× speedup compared to a serial implementation. Results show that as the query length increases our speedup almost stays stable indicating the solid scalability of our approach. Additionally this is a first of a kind implementation which purely runs on the GPU instead of a CPU-GPU integrated environment, making our design suitable for porting onto a cluster of GPUs.A. Akoglu ( ) · G.M. Striemer

A node and network level self-recovering distributed wireless sensor architecture for real-time crop monitoring in greenhouses (2011) Transactions of the ASABE, 54 (4), pp. 1521-1527. Cited 1 time.

The DNA recombination process known as V(D)J recombination is the central mechanism for generating diversity among antigen receptors such as T-cell receptors (TCRs). This diversity is crucial for the development of the adaptive immune system. However, modeling of all the α β TCR sequences is encumbered by the enormity of the potential repertoire, which has been predicted to exceed 10 15 sequences. Prior modeling efforts have, therefore, been limited to extrapolations based on the analysis of minor subsets of the overall TCRβ repertoire. In this study, we map the recombination process completely onto the graphics processing unit (GPU) hardware architecture using the CUDA programming environment to circumvent prior limitations. For the first time, we present a model of the mouse TCRβ repertoire to an extent which enabled us to evaluate the Convergent Recombination Hypothesis (CRH) comprehensively at peta-scale level on a single GPU.

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