Energy-Efficient Computations on FPGAs

Abstract

Recently, energy dissipation for computations on FPGAs has become an important performance metric. In this paper, we summarize our recent efforts in developing an algorithm-level design methodology for optimizing the energy performance of FPGA based implementations. For kernels, our design methodology consists of four steps: domain selection, domain-specific energy modeling, domain-space exploration and low-level simulation. To achieve system-level energy-efficiency, we outline a design methodology that integrates the kernel-level design methodology. Both the design methodologies can be used to achieve not only energy-efficiency but also latency, area, and power efficiency. We consider signal processing kernels as illustrative examples and demonstrate energy and time efficient algorithms and implementations for these on FPGAs. Example energy performance optimization through algorithmic optimizations include the 29–51% improvement in energy performance for a matrix multiplication kernel, 57–78% improvement for a FFT kernel and the 10–60% improvement for a floating-point LU decomposition kernel over state-of-the-art implementations. Similarly, an improvement of 41 to 46% in energy performance was achieved by the system-level design approach over a greedy approach for a MVDR adaptive beamforming application. Finally we briefly describe a high-level tool for obtaining parameterized and energy-efficient designs on FPGAs.