First release candidate of Linux 3.0 available
It was already on the cards last week, and now it's official: the next kernel of the Linux main development branch is to be given version number 3.0, as explained by Linus Torvalds in his release email for the first RC of the new version. The final 3.0 release is expected in about seven to nine weeks. With this release candidate, the kernel's name has also been changed from "Flesh-Eating Bats with Fangs" to "Sneaky Weasel".
Being the successor of Linux 2.6.39, which was released eleven days ago, the version in the current development cycle would have been called 2.6.40. Since the release of version 2.6.0 almost seven and a half years ago, and the subsequent decision to abandon the development of "unstable series" such as 2.3 and 2.5, the kernel hackers simply kept incrementing the kernel's three-figure version number. However, in a surprise move a few days ago, Linus Torvalds said that the "voices in his head" had told him that the numbers are getting too big. It was in this context that Torvalds mentioned he was considering a jump to 2.8.0, but the resulting discussions soon revolved around version 3.0.
The leading "3" is to designate the third decade, which Linux will enter soon – the kernel will be 20 years old later this year. The successor of version 3.0 is to be called 3.1 and will probably be released two to three months after 3.0. In future, the versions in the Stable and Long-term series that are developed in parallel with the main development line will be able to use the third part of the version number to identify their kernels; they previously used a fourth part. Various scripts in the kernel and its environment still need to be adapted to this change; this is one of the reasons why the release candidate is currently called 3.0.0-rc1, rather than 3.0-rc1, in various places. Linus Torvalds has created a new directory for the version 3.0 kernels at kernel.org; the scripts for the site's home page have not been full adapted and don't yet link to the Linux 3.0-rc1 archives.
In his release email for 3.0-rc1, Torvalds writes that jumping to version 3.0 was a decision he made by himself. He also emphasised that this version will offer no major changes. "The point is that 3.0 is *just* about renumbering" said Torvalds, adding that the new version won't offer big changes unlike, for instance, KDE 4 and GNOME 3 did. Last week he explained to other kernel hackers that he wasn't going to use the milestone version jump to make any specific major changes or drop such supposed legacies as the kernel's MCA, EISA or ISA support (1, 2).
However, the release candidate of 3.0 does contain the usual flurry of advancements, as these were developed and submitted by many other kernel hackers even before the discussions about a 3.0 version jump began. Unexpectedly, the changes do include the Xen storage backend. This means that the kernel now contains all the components needed to run as a management domain (Dom0) kernel under the Xen hypervisor; some background on this is available in a blog posting by Oracle employee Wim Coekaerts.
The Linux 3.0 netfilter code now contains a Just-In-Time compiler for x86-64 systems that is said to enhance the kernel's performance in terms of firewall packet processing. The developers have also made numerous further improvements to the still-experimental Btrfs file system. As usual, they have also added a few dozen new drivers to the kernel, including the rtl8192se driver for Wi-Fi chips by Realtek and a driver for the Micronas DRXD DVB-T tuner, which is used by various vendors. Over the coming weeks, the Kernel Log on The H will discuss these and many further advancements in Linux 3.0.