Kernel 2.6.29: Corbet Says Btrfs Next Generation Filesystem
Linux kernel developer Jonathan Corbet has just previewed the features of the upcoming Linux Kernel 2.6.29 that includes Btrfs, which he claims is the filesystem of the future.
In time for the holidays, Linus Torvalds had released Kernel 2.6.28, which was followed promptly within two weeks by the first candidate for 2.9.29. Kernel maven Jonathan Corbet, in his Linux Foundation blog, sees a lot of work ahead for the new release, albeit with a "relatively small list of exciting new features." As he writes, "First and foremost for many people will be the addition of the Btrfs filesystem." On January 5th, Chris Mason had appealed for its inclusion in the kernel, prompting considerable feedback. Corbet tried to end any further speculation by promising that Btrfs has a great future ahead for it: "Btrfs is intended to be the next-generation filesystem which, conceivably, could last us for the next 10-20 years." To be sure, Btrfs is not yet the filesystem of choice for the kernel and is still "under heavy development." As Corbet says, "Nobody should be expecting to use Btrfs for any data they care about for the next year - at least." As to why Btrfs is already in the kernel mainline, Corbet responds that it would thereby "approach production-readiness more quickly" through user and developer testing.
Corbet also continues to support the staging tree concept introduced in the summer of 2008 as an experimental kernel branch. The staging tree adopts new drivers that might not be ready for prime time, but nonetheless make certain hardware run under Linux. Corbet has already seen some successes: "Early experience shows that staging-tree drivers do, indeed, see fixes for a lot of problems which have remained unfixed for years previously." He cites as examples the Google Android driver and the Ralink wireless interfaces, which run on the popular Asus Eee PC.
Other visible enhancements to 2.6.29 that Corbet mentions are patches for the kernel-mode setting (KMS) for video and 3D graphic support on x86 systems. As for this "very new" code, Corbet still warns that it supports only a few Intel adapters and requires the appropriate version of X Server. The new kernel also incorporates the read-only Squashfs filesystem mainly used in live CD distributions and embedded systems.
With the stabilization process having begun for the first release candidate, Corbet promises "a surprise or two" for testers: "Over the next two months, these problems will be found and fixed, setting the stage for a stable 2.6.29 release sometime in March."