This turned out to be much less of a problem than I'd expected - whether because of their enthusiasm to learn about ACPI or because they simply hadn't noticed the alert telling them about the cancellation, a decent body of students turned up the next morning. After a brief chat with Mark Stehlik, the assistant dean for undergraduate education, I headed off to the lecture hall. The fact that I can now just plug my laptop into a VGA cable and have my desktop automatically extend itself continues to amaze me, as does OpenOffice's seemingly unerring ability to get confused about which screen should have my content and which should be showing me the next slide. Nevertheless, facts were imparted and knowledge dropped on those assembled. I'm even reasonably sure that the contents were factually accurate, which is a shame because the most attractive part of teaching always struck me as being able to lie to students who will then happily regurgitate whatever you tell them because in case it turns up on the exam. Perhaps this is why I'm safer out of academia.
Lunch offered an opportunity to visit the Red Hat sponsored lab, which was pleasingly located somewhere other than a basement. The guy on the right of the picture is Greg Kesden, the director of undergraduate laboratories in CS there - it was wonderful to get an opportunity to see the machines getting used, and students seemed genuinely appreciative of the facility.
After lunch I spent a while talking to Satya about the Internet Suspend and Resume project. This is an impressive combination of virtualisation and migration, using a Fedora-based live image to bring up an OS on arbitrary hardware before downloading a machine image and launching it. The majority of the data is pulled in on demand, meaning that initial performance can be slow but ensuring that data is only downloaded if it's needed. When the user is finished, the delta between the original image and the new one can be pushed back to the server while remaining cached on the local machine in case the image is used again.
It's an interesting approach, combining the flexibility of thin clients with the advantages of having actually useful computing power at the local end. There's a few functional awkwardnesses, such as some VMs being unhappy if images are migrated between machines with different CPU features, and it obviously benefits from having significant bandwidth. But the idea of being able to combine the convenience of a floating session with the knowledge that you can still keep copies of your data on you is an attractive one, and I'd love a future where I can move my session between my laptop and a desktop.
After that there was some time to talk to Bill Scherlis and Philip Lehman about the software engineering courses that CMU run. Part of the minor in software engineering includes a course requirement to make a meaningful contribution to an existing software project, from design through to submission and upstream acceptance. I had the opportunity to talk to a couple of the students about this and the differences they found between working with the Mozilla and Chrome communities, which I'll try to write up at some point.
Finally I gave a presentation on Fedora and some of the issues that we face in providing a useful OS when patents and recalcitrant hardware vendors do their best to thwart us. Despite the ice outside and the significantly-below-freezing temperatures, enough people turned up that sorties had to be sent out to find extra chairs. It was great to see how interested people were in learning about what we do, although it's probably the case that the free pizza did help encourage people.
After that it was an early trip back to the airport, where I found that my plane was delayed and the only "restaurant" still open was McDonalds. Even so, I left with the feeling that it had been an interesting and educational visit. Many thanks to David Eckhardt, who runs the OS course I presented to and who looked after me all day - thanks too to Joshua Wise who picked me up when David was running late due to the ground being covered with blocks of ice.