The effectiveness of the last-level shared cache is crucial

to the performance of a multi-core system. In this paper,

we observe and make use of the DelinquentPC—Next-Use

characteristic to improve shared cache performance. We

propose a new PC-centric cache organization, NUcache,

for the shared last level cache of multi-cores. NUcache

logically partitions the associative ways of a cache set into

MainWays and DeliWays. While all lines have access to the

MainWays, only lines brought in by a subset of delinquent

PCs, selected by a PC selection mechanism, are allowed to

enter the DeliWays. The PC selection mechanism is an intelligent

cost-benefit analysis based algorithm that utilizes

Next-Use information to select the set of PCs that can maximize

the hits experienced in DeliWays.

Performance evaluation reveals that NUcache improves

the performance over a baseline design by 9.6%, 30%

and 33% respectively for dual, quad and eight core workloads

comprised of SPEC benchmarks. We also show that

NUcache is more effective than other well-known cachepartitioning

algorithms.

In  Proceedings of the International Conference on High Performance Computer Architecture (HPCA), 2011

Publisher  IEEE

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