基于决策树的间接访存数据预取激进度调节方法OA

Indirect memory access(IMA)is a prevalent memory access pattern in general-purpose processors,and nu-merous prefetchers dedicated to handling indirect memory accesses have been developed.Although these prefetch-ers significantly improve the performance of processors in single-core systems,we have observed that the aggressive prefetching configurations used in single-core systems do not yield the same level of performance improvement in multi-core systems.This discrepancy is primarily attributed to the different memory bandwidth demands between single-core and multi-core systems,which result in varying optimal levels of prefetching aggressiveness.The exist-ing methods for adjusting prefetching aggressiveness mostly involve manual setting of adjustment rules,which is not only inefficient but also prone to inaccuracies in adjustment strategies.To address these issues,this paper intro-duces the DTPAC(decision tree-based prefetcher aggressiveness controller),a method for automatically adjusting the aggressiveness of prefetchers for indirect memory accesses using decision tree algorithms,thereby avoiding the drawbacks of manual rule-setting.Experimental results demonstrate that on the indirect memory access prefetcher Tyche,DTPAC improves performance by 13.2%in a quad-core system,outperforming existing methods such as FDP and CLIP.Additionally,DTPAC reduces memory traffic by 20.0%.Furthermore,in a quad-core system,DTPAC also enhances the performance of two other indirect memory access prefetchers,Gretch and IMP,by 6.8%and 5.5%,respectively.