Title
A study on polymorphing superscalar processor dynamically to improve power efficiency
Abstract
Asymmetric Multicore Processors (AMP) have emerged as likely candidates to solve the performance/power conundrum in the current generation of processors. Most recent work in this area evaluate such multicores by considering large (usually out-of-order (OOO)) and small (usually in-order (InO)) cores on the same chip. Dynamic online swapping of threads between these cores is then facilitated whenever deemed beneficial. However, if threads are swapped too often, the overheads may negatively impact the benefits of swapping. Hence, in most recent work, thread swapping decisions are made at coarse grain instruction granularities, leaving out many opportunities. In this paper, we propose a scheme to mitigate the penalty imposed by thread swapping and yet achieve all the benefits of AMPs. Here, a single superscalar OOO core morphs itself into an InO core at runtime, whenever determined to be performance/Watt efficient. Certain Intel processors already have a similar mechanism to statically morph an OOO core to an InO core to facilitate debug. We extend this existing capability to perform dynamic core morphing at runtime with an orthogonal objective of improving power efficiency. Results indicate that on an average, performance/Watt benefits of 10% can be extracted by our proposed morphing scheme at a very small performance penalty of 3.8%. Since this scheme is based on existing mechanisms readily available in current microprocessors, it incurs no hardware overheads.
Year
DOI
Venue
2013
10.1109/ISVLSI.2013.6654621
ISVLSI
Keywords
Field
DocType
asymmetric multicore processor,asymmetric multicore processor (amp),online swapping,microprocessor chips,power efficiency,in-order (ino),small in-order core,low-power electronics,superscalar out-of-order core,core morphing,multiprocessing systems,large out-of-order core,dynamic core morphing,out-of-order (ooo),polymorphing superscalar processor,thread swapping,low power electronics
Electrical efficiency,Computer science,Scheduling (computing),Parallel computing,Thread (computing),Multi-core processor,Out-of-order execution,Benchmark (computing),Embedded system,Low-power electronics,Debugging
Conference
ISSN
Citations 
PageRank 
2159-3469
1
0.34
References 
Authors
24
5
Name
Order
Citations
PageRank
Sudarshan Srinivasan1335.01
R. Rodrigues211110.56
Arunachalam Annamalai3845.67
Israel Koren41579175.07
Sandip Kundu51103137.18