Wednesday started with a session on power savings on multi-core ARM using cgroups. The gist is that cgroups allow assigning all running processes to one or more cores, allowing the other cores to go into an idle state and not draw power. The one problem they’re noticing with this scheme is that sometimes IRQs or timers are assigned to a CPU that is supposed to be idle, leading to more frequent wakeups and higher power draw. The Linaro guys are working on this issue but even without solving it they are seeing 90% of the power savings compared to CPU hotplug. (blueprint, notes)

Following that I went to a session on server management on ARM. Mostly it was an attempt to list the various multi-server management tools that are in use today and  figure out if they are broken on ARM. There was also some discussion about DMI, which is useful for servers but only available on Intel platforms. The interface will need to be replicated or something equivalent will need to be created for some of the server tools to work. (blueprint, with notes)

Next was a lecture by Vincent Guittot of Linaro about potential power savings to be found when the multicore/cluster scheduler is tuned to be aware of power consumption as well as performance concerns. Unfortunately the presenter was supposed to dial in but the conference phone wasn’t working. He dialed in to someone’s cell on speaker but it was so hard to hear that the presentation itself was nearly worthless. The good news is that they put up slides[odp] and a wiki page with the relevant information.

Last session before lunch was on the upcoming enhancements to Thunderbird to make it easier to use as well as fit in better with the Ubuntu desktop. Upcoming changes include simplifying the message list by getting rid of redundant information and getting rid of the confusing multiple search and filtering boxes in the main UI. You can actually follow along with the development process at the Thunderbird project’s Tumblr site. (blueprint, notes)

After lunch was a plenary session with two presentations. First a representative from ARM went over the current ecosystem around their platform and the upcoming changes in ARMv8. Then we had a speaker from OIN talk about defensive patents and the current state of software patents in general. Finally they took everybody outside (under the Daystar!) to take a group photo. Considering how tightly the 700 or so of us were packed I thought the jump shot was a bit on the dangerous side.

Back to the normal sessions, I went to a discussion on enabling folks to more easily customize Unity, specifically helping derivative distributions, OEMs and corporate customers get the experience they want out of the box for their users. I was happy to hear that many settings which are currently stored all over the place will be consolidated into gsettings. (blueprint, notes)

Next I attended a workshop on Qt Quick. It was a nice demonstration on the kinds of interfaces you can design using Qt Quick’s declarative QML language. They were very careful to emphasize a separation between logic (C++ or python) and presentation (QML).

Last session of the day was a planning session for Ubuntu on phones. The discussion largely centered around the problems which arise when trying to move from a full desktop environment to a phone interface, from memory requirements and touch interface to what framework to use for phone functionality and location services. (blueprint, notes)

In the evening we had a small gathering for our group with drinks and hors d’oeuvre. Not being satisfied with that a bunch of us walked about a mile along the side of a highway to get to an Irish pub in a nearby strip mall. We ate, drank, and made merry then headed back to the hotel (some folks wimped out and took a cab) for more of the same.

UDS-P Orlando Day 3 by ssweeny.net is licensed under a Creative Commons Attribution 4.0 International License.