Performance and power evaluation of an in-line accelerator

In this paper we evaluate the performance and power of a processor-attached in-line accelerator. The accelerator provides high-performance SIMD computing and power efficiency by means of a very large register file and a set of vector multimedia extensions based on IBM's PowerPC VMX. Our experiments show significant performance improvements and power reduction, compared to a baseline vector execution unit, mainly due to the drastic decrease of memory accesses caused by the software-managed locality of the very large register file. Total execution time is, on average, reduced by 61%, while consuming 55% less energy.