Reducing non-deterministic loads in low-power caches via early cache set resolution

摘要

Many of the recently proposed techniques to reduce power consumption in caches introduce an additional level of non-determinism in cache access latency. Due to this additional latency, instructions dependent on a load speculatively issued must be squashed and re-issued as they will not have the correct data in time. Our experiments show that there is a large performance degradation and associated dynamic energy wastage due to these effects of instruction squashing. To address this problem, we propose an early cache set resolution scheme. Our experimental evaluation shows that this technique is quite effective in mitigating the problem.