Performance Portable FPGA Design.

FPGA platforms are widely used for application acceleration. Although a number of high-level design frameworks exist, application and performance portability across different platforms remain challenging. To address the above problem, we propose an API design for high-level development tools to separate platform-dependent code from the remaining application design. Additionally, we propose design guidelines to assist with performance portability. To demonstrate our techniques, a large-scale application, originally developed for an Intel Stratix-V FPGA is ported to several new Xilinx Virtex UltraScale+ systems. The accelerated application, developed in a high-level framework, is rapidly moved onto the new platforms with minimal changes. The original, unmodified kernel code delivers a 1.74x speedup due to increased clock frequency on the new platform. Subsequently, the application is further optimised to make use of the additional resources available on the larger Ultrascale+ FPGAs, guided by a simple analytical performance model. This results in an additional performance increase of up to 7.4x. Using the presented framework, we demonstrate rapid deployment of the same application across a number of different platforms that leverage the same FPGA family but differ in their low-level implementation details and the available peripherals. As a result, the same application code supports five different platforms: Maxeler MAX5C DFE, Amazon EC2 F1, Xilinx Alveo U200, U250 and the original Intel Stratix-V accelerator card, with performance close to what is theoretically achievable for each of these platforms.