Here are a few short descriptions of some research projects that I’ve worked on recently.
The power consumption of CPUs and memory systems has traditionally been constrained by the need for strict correctness guarantees: processor voltage, for instance, must allow enough slack as to prevent even the rarest timing errors. But many modern applications do not require perfect correctness. An image renderer, for example, can tolerate occasional pixel errors without compromising overall quality of service. However, it is infeasible to completely abandon correctness guarantees—to do so would make development of reliable software difficult or impossible. EnerJ is a programming language that exposes hardware faults in a safe, principled manner. Simulation of selectively reliable hardware suggests that EnerJ programs can save large amounts of energy with only slight sacrifices to quality of service.
Automatic Discovery of Performance and Power Pitfalls in Web Browsers
Web browsers’ speed and power consumption have become salient concerns with the emergence of Web-enabled mobile devices. However, the relationship between page content and browser performance is poorly understood. WebChar uses machine learning to automatically discover correlations between page characteristics and browser behavior. The results can help content providers deploy better-performing Web sites and assist browser developers in optimizing their implementations.
Explicit Shared-Memory Communication
Shared memory is a fast, simple, and ubiquitous model for multiprocessor computing. However, shared-memory programs are prone to subtle, hard-to-diagnose concurrency bugs. Much of this difficulty arises because cross-thread communication in shared-memory programs is transparent and not easily apparent to the programmer. Organized Sharing (OSHA) consists of a language extension that makes communicating code explicit and an implementation (“OSHAJava”) of a high-performance dynamic checker that can catch concurrency bugs in annotated programs before they cause problems.
Look me up at DBLP for another view on my publications. Where possible, the titles below are “magic” links to the ACM database server that should let you view the PDF for free while letting the ACM keep track of viewer statistics. Use the “local PDF” links if you prefer bypass this rigmarole.
- “Neural Acceleration for General-Purpose Approximate Programs.” Hadi Esmaeilzadeh, Adrian Sampson, Luis Ceze, and Doug Burger. In MICRO 2012.
- “Automatic Discovery of Performance and Energy Pitfalls in HTML and CSS.” Adrian Sampson, Călin Caşcaval, Luis Ceze, Pablo Montesinos, and Dario Suarez Gracia. Poster and extended abstract in IISWC 2012.
- “Architecture Support for Disciplined Approximate Programming.” Hadi Esmaeilzadeh, Adrian Sampson, Luis Ceze, and Doug Burger. In ASPLOS 2012.
- “EnerJ: Approximate Data Types for Safe and General Low-Power Computation.” Adrian Sampson, Werner Dietl, Emily Fortuna, Danushen Gnanapragasam, Luis Ceze, and Dan Grossman. In PLDI 2011.
- “Composable Specifications for Structured Shared-Memory Communication.” Benjamin Wood, Adrian Sampson, Luis Ceze, and Dan Grossman. In OOPSLA 2010. Local PDF.
- “On-line Distributed Traffic Grooming.” R. Jordan Crouser, Brian Rice, Adrian Sampson, and Ran Libeskind-Hadas. In ICC 2008.
- Design Tradeoffs of Approximate Analog Neural Accelerators. Renée St. Amant, Hadi Esmaeilzadeh, Adrian Sampson, Luis Ceze, Arjang Hassibi, and Doug Burger. In NIAC 2013.
- “Addressing Dark Silicon Challenges with Disciplined Approximate Computing.” Hadi Esmaeilzadeh, Adrian Sampson, Michael Ringenburg, Dan Grossman, Luis Ceze, and Doug Burger. In DaSi 2012 (co-located with ISCA).
- “Towards Neural Acceleration for General-Purpose Approximate Computing.” Hadi Esmaeilzadeh, Adrian Sampson, Luis Ceze and Doug Burger. In WEED 2012 (co-located with ISCA).
- “Greedy Coherence.” Emily Fortuna, Brandon Lucia, Adrian Sampson, Benjamin Wood and Luis Ceze. In HPPC 2011 (co-located with MICRO).
- “Dense Approximate Storage in Phase-Change Memory.” Jacob Nelson, Adrian Sampson, and Luis Ceze. Presented in the Ideas & Perspectives session at ASPLOS 2011.