Calendar

Current Events

3.30

Creating a Sustainable Society

3.16

Sustainable Energy Engineering

2.28

National Science Foundation Day

2.17

Reformulation-Based Approaches to Query Optimization

2.15

FREEDM Day

2.10

WEST: Cloning Data Cache Behavior using Stochastic Traces

2.09

Computer Vision and Image Analysis in the Study of Art

2.08

GSA Social

2.03

Skewed functional processes and their applications

CAP: Criticality Analysis For Power-Efficient Speculative Multithreading

Abstract:

While Speculative Multithreading (SM) on a Chip Multiprocessor (CMP) has the ability to speed-up hard-to-parallelize applications, the power inefficiency of aggressive speculation is a concern. To improve SM’s power efficiency, we note that not all the tasks that are running in a SM environment are equally critical.

To leverage this insight, this talk will propose a novel, widely-applicable task-criticality model for SM, and, CAP, a novel architecture that builds a task-criticality graph dynamically and uses it to make scheduling decisions in a SM CMP. Experiments with SPECint, SPECfp, and Olden applications show that, in a CMP with one fast core and three slow ones, the E x D^2 with CAP is, on average, 91–95% of that without. Moreover, it is only 77–91% of the ExD^2 of a CMP with four fast cores and no CAP. Overall, scheduling for task criticality is beneficial.