With the release of Linux kernel 2.6.9-rc1, Linus Torvalds further refined the new kernel development model [story] first proposed at the 2004 kernel summit [story]. The earlier 2.6.8 kernel was quickly followed by 2.6.8.1 [story] to address an oops in NFS. With today's 2.6.9-rc1 Linus explained, "administrative trivia, and one thing I agonized over: should I make the patches relative to 2.6.8 or 2.6.8.1? I decided that since there is nothing that says that 'basic bug-fix' releases for a previous release might not happen _after_ we've done a -rc release for the next version, I can't sanely do patches against a bugfix release."

With Linus having returned from a week-long vacation, he noted that there were "tons of patches merged", specially thanking Andrew Morton [interview] "who synced up 200+ patches". Regarding the specific changes in this release candidate, Linus said they are "all over: arm, ppc, sparc, acpi, i2c, usb, fbcon, ntfs, xfs, nfs, cpufreq, agp, sata, network drivers - you name it. Most of the changes are fairly small, but there's a lot of them."

With the release of 2.6.8.1-mm2, in addition to a probable fix for the memory leak some reported when writing audio CDs [story], Andrew Morton [interview] announced that the long awaited [story] Resier4 filesystem has been merged into his -mm patchset [story]. Hans Reiser provided some information about the history and usage of Reiser4, beginning:

"Reiser4 is a file system based on dancing tree algorithms, and is described at http://www.namesys.com. One should be able to get it up and running just like any of the other filesystems supported by Linux. Configure it to be compiled either builtin or as a module. Create reiser4 filesystem with mkfs.reiser4, mount and use it. More detailed info can be found at http://thebsh.namesys.com/snapshots/LATEST/READ.ME."

In question and answer format - questions from Andrew, answers from Hans - we go on to learn where to obtain the latest Reiser4 tools, and about the current limitations of the filesystem. Hans explains, "Reiser4 has [only] been tested on i386 [...]. Quota support is not ready yet. Should be ready soon. [...] Only the very core functionality is working. Exotic plugins, an API for multiple operation transactions and accessing multiple small files in one syscall, compression, inheritance, all have been postponed until after the core functionality is shipped." Read on for more information, including tips on benchmarking the new filesystem.