Accelerating re-pair compression using FPGAs

Abstract

Re-Pair is a compression algorithm well-suited for applications that require random accesses to compressed data, but has not found widespread use in the data management community due to its prohibitively high compression times. As Re-Pair is a computationally expensive algorithm and FPGAs are becoming more and more common to accelerate such problems in data centers, we devise an FPGA system that performs Re-Pair compression. The system is implemented in OpenCL, aside from a hash table and sorting component realized in RTL for more control over the synthesized hardware. Our experiments demonstrate that an Intel Arria® 10 GX FPGA with our system compresses an order of magnitude faster than a highly-optimized CPU version of Re-Pair. We discuss further optimization opportunities and argue that our system can scale to being deployed on a more resourceful FPGA for even better performance.