[Colloquium] Reminder: Imes/MS Presentation/Feb 20, 2015

[Margaret Jaffey]

This is a reminder about Connor's MS Presentation tomorrow.

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Date:  Friday, February 20, 2015

Time:  2:30 PM

Place:  Ryerson 251

M.S. Candidate:  Connor Imes

M.S. Paper Title: Managing Diversity in Performance and Energy
Characteristics on Embedded Systems

Abstract:
Minimizing energy under timing constraints is a common task for
embedded systems, which are often limited by available energy sources.
Solving this problem even for a single system is hard, and current
solutions are often designed for specific platforms and applications.
Developing general techniques is difficult because of the variety in
performance, power, and energy characteristics of different systems
and applications. While heuristic solutions have often sufficed in the
past, the increase in configurability and heterogeneity of modern
systems means that no single heuristic will perform well on all
platforms, or even for all applications on a single platform. A
portable solution to the problem is needed.

This thesis first identifies two embedded systems that expose
different performance/power and latency/energy tradeoff spaces and
demonstrates that each requires a different heuristic to achieve
acceptable energy consumption under timing constraints. Both systems
use hardware designs that are common in today’s cutting-edge devices,
thus establishing the problem as a genuine concern for system and
software designers. The first is a Sony Vaio tablet, a homogeneous
multi-core system with a mobile Intel Haswell processor; the second is
an ODROID development platform, a single-ISA heterogeneous multi-core
system with an ARM big.LITTLE processor. We show that the Vaio
requires a race-to-sleep heuristic to achieve acceptable energy
efficiency while the ODROID requires a never-idle heuristic, and that
choosing the wrong strategy can increase energy consumption as much as
14× the optimal. To address this problem, we present POET, a portable
library and runtime that manages system resources to achieve
near-optimal energy consumption while meeting soft real-time
performance constraints. We show that POET meets performance targets
with small error while consuming, on average, only 1.3% more energy on
the Vaio compared to a dynamic optimal oracle, and 2.9% more on the
ODROID. POET is designed to facilitate writing portable,
energy-efficient applications by providing a simple and extensible API
to users. It is released as open-source software under the BSD
License.

Connor's advisor is Prof. Henry Hoffmann

Login to the Computer Science Department website for details:
 https://www.cs.uchicago.edu/phd/ms_announcements#ckimes

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Margaret P. Jaffey            margaret at cs.uchicago.edu
Department of Computer Science
Student Support Rep (Ry 156)               (773) 702-6011
The University of Chicago      http://www.cs.uchicago.edu
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