The Kernel Summit was preceded by the 13th Real Time Linux Workshop, also in Prague. The organisers have now made proceedings of many of the presentations on real-time Linux available online, including papers on robot control systems, simulations and process scheduling.
A get-together involving many of the key developers behind real-time support for Linux was held on the final day of the event. LWN.net carries a report on the major points from this meeting, which included discussions on the roadmap for the software interrupt code (softirq) and on per CPU data structures.
The issue of when the major real-time support changes would find their way into the mainline Linux kernel was also raised. The real-time tree contains a whole series of changes which are set to be merged into the mainline soon – in some cases as soon as Linux 3.2. There are, however, some problem areas for which proper solutions still need to be found. These include support for generating good random numbers, which is partly disabled in the real-time tree. There has been little progress in the deadline scheduler, designed for real-time use, as the developer responsible for it has been busy doing other things.
Next year's workshop will be held at the Department of Computer Science at the University of North Carolina.
Kernel version status
Since releasing Linux 3.1 last Monday, Torvalds has already merged more than 8500 changes lined up for Linux 3.2. The volume of changes is unusually large, with diffstat already reporting the addition of more than 1.5 million lines of code and the removal of about 1.3 million – more than in any kernel version since Linux 2.6.0. One reason for the high numbers is the relocation of large segments of code for network drivers – relocated code is included in both of the above figures. The prolonging of the Linux 3.1 development period has also meant the number of changes awaiting merger has been piling up.
There is not yet a stable Linux 3.1 kernel, with the latest stable kernel being version 3.0.8, released on October 27. It and other stable kernels are now again available from kernel.org, which since a few days presents a mostly up to date front page again. The authenticity of the archive with the latest stable kernels can be checked using the measures described in the The H article on Linux 3.1.