Instruction distribution heuristics for quad-cluster, dynamically-scheduled, superscalar processors

We investigate instruction distribution methods for quadcluster, dynamically-scheduled superscalar processors. We study a variety of methods with different cost, performance and complexity characteristics. We investigate both non-adaptive and adaptive methods and their sensitivity both to inter-cluster communication latencies and pipeline depth. Furthermore, we develop a set of models that allow us to identify how well each method attacks issue-bandwidth and inter-cluster communication restrictions. We find that a relatively simple method that changes clusters every other three instructions offers only a 17% performance slowdown compared to a nonclustered configuration operating at the same frequency. Moreover, we show that by utilizing adaptive methods it is possible to further reduce this gap down to about 14%. Furthermore, performance appears to be more sensitive to inter-cluster communication latencies rather than to pipeline depth. The best performing method offers a slowdown of ...

• Type: Conference
• Year: 2000
• Where: MICRO
• Authors: Amirali Baniasadi, Andreas Moshovos
• Keywords: Adaptive Methods, Hardware, Inter-cluster Communication, Inter-cluster Communication Latencies, MICRO 2000