Chip Design

Vol. 8 No. 2 – February 2010

Chip Design

Commitment Issues

When is the right time to commit changes?

Commitment Issues

When is the right time to commit changes?

Dear KV,

One of the other people on my project insists on checking in unrelated changes in large batches. When I say unrelated, what I mean is he will fix several unrelated bugs and then make a few minor changes to spacing and indentation across the entire source tree. He will then commit all of these changes at once, usually with a short commit message that lists only the bugs he claims to have fixed. Do you think I'm being too picky in wanting each checkin to address only one issue or problem?

by George Neville-Neil

Articles

Toward Energy-Efficient Computing

What will it take to make server-side computing more energy efficient?

Toward Energy-Efficient Computing

David J. Brown, Sun Microsystems

Charles Reams, Cambridge University

What will it take to make server-side computing more energy efficient?

By now, most everyone is aware of the energy problem at its highest level: our primary sources of energy are running out, while the demand for energy in both commercial and domestic environments is increasing, and the side effects of energy use have important global environmental considerations. The emission of greenhouse gases such as CO2, now seen by most climatologists to be linked to global warming, is only one issue.

The world's preeminent scientists and thought leaders are perhaps most focused on a strategic solution: the need to develop new sources of clean and renewable energy if we are ultimately to overcome the energy problem. Lord Rees, president of the Royal Society, emphasized its urgency in an annual address delivered in 2008.13

by David J. Brown, Charles Reams

Interviews

A Conversation with Steve Furber

The designer of the ARM chip shares lessons on energy-efficient computing.

Conversation with Steve Furber

The designer of the ARM chip shares lessons on energy-efficient computing.

If you were looking for lessons on energy-efficient computing, one person you would want to speak with would be Steve Furber, principal designer of the highly successful ARM (Acorn RISC Machine) processor. Currently running in billions of cellphones around the world, the ARM is a prime example of a chip that is simple, low power, and low cost. Furber led development of the ARM in the 1980s while at Acorn, the British PC company also known for the BBC Microcomputer, which Furber played a major role in developing.

In our interview this month he shares some of the lessons on energy-efficient computing he has learned through working on these and subsequent projects. He also fills us in on the innovative work he is doing at Manchester University, where he is a professor of computer engineering in the School of Computer Science. Furber's SpiNNaker (Spiking Neural Network Architecture) project is a massively parallel system designed to simulate the workings of part of the human brain. Composed of a million ARM processors, SpiNNaker could help unravel some of the mysteries of the brain and eventually could provide valuable lessons on energy-efficient, fault-tolerant computation.