An efficient single-pass trace compression technique utilizing instruction streams

Abstract

Trace-driven simulations have been widely used in computer architecture for quantitative evaluations of new ideas and design prototypes. Efficient trace compression and fast decompression are crucial for contemporary workloads, as representative benchmarks grow in size and number. This article presents Stream-Based Compression (SBC), a novel technique for single-pass compression of address traces. The SBC technique compresses both instruction and data addresses by associating them with a particular instruction stream, that is, a block of consecutively executing instructions. The compressed instruction trace is a trace of instruction stream identifiers. The compressed data address trace encompasses the data address stride and the number of repetitions for each memory-referencing instruction in a stream, ordered by the corresponding stream appearances in the trace. SBC reduces the size of SPEC CPU2000 Dinero instruction and data address traces from 18 to 309 times, outperforming the best trace compression techniques presented in the open literature. SBC can be successfully combined with general-purpose compression techniques. The combined SBC-gzip compression ratio is from 80 to 35,595, and the SBC-bzip2 compression ratio is from 75 to 191,257. Moreover, SBC outperforms other trace compression techniques when both decompression time and compression time are considered. This article also shows how the SBC algorithm can be modified for hardware implementation with very modest resources and only a minor loss in compression ratio.