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Zack's Kernel News KERNEL NEWS ZACK’S KERNEL NEWS ReiserFS Turmoil Their longer term plan, Alexander Multiport Card driver, again naming In light of recent events surrounding says, depends on what happens with himself the maintainer. Hans Reiser (http:// www. linux-maga- Hans. If Hans is released, the developers Jiri’s been submitting a number of zine. com/ issue/ 73/ Linux_World_News. intend to proceed as before. If he is not patches for these drivers, so it makes pdf), the question of how to continue released, Alexander’s best guess is that sense he would maintain them if he ReiserFS development came up on the the developers will try to appoint a wished; in any event, no other kernel linux-kernel mailing list. Alexander proxy to run Namesys. hacker has spoken up to claim the role. Lyamin from Hans’s Namesys company offered his take on the situation. He said Status of sysctl Filesystem Benchmarks that ReiserFS 3 has pretty much stabi- In keeping with Linus Torvalds’ recent Some early tests have indicated that ext4 lized into bugfix mode, though Suse assertions that it is never acceptable to is faster with disk writes than either ext3 folks had been adding new features like break user-space, Albert Cahalan volun- or Reiser4. There was general interest in ACL support. So ReiserFS 3 would go on teered to maintain the sysctl code if it these results, though the tests had some as before. couldn’t be removed. But Linus pointed problems (the tester thought delayed In terms of Reiser4, however, Alexan- out that really nothing actually used allocation was part of ext4, when that der said that he and the other Reiser de- sysctl (the implication being that it feature has not yet been merged into velopers were still addressing the techni- wouldn’t actually break anything to get Andrew Morton’s tree). cal issues, and continuing to work, rid of it). Andrew Morton also remarked, Various folks also requested that the largely with Andrew Morton in his 2.6 “It should always be an objective to re- tests be expanded to include other file- tree. Their plan for developing ReiserFS move code if we can feasibly find a way systems; and Theodore Ts’o suggested over the next six months is apparently to to do so. For us to give up now and to converting these tests into something continue in this vein, at the same time leave all that goop in there forever would that could be automated, for future com- also seeking outside business opportuni- be sad.” parisons between individual filesystem ties to stay funded. So unless something comes up, like a features. But he acknowledged that this big user-space application that really de- might entail an arbitrarily large quantity The Linux kernel pends on sysctl, it does seem as though of work. And the original poster con- mailing list com- that code may eventually be removed firmed that the task of automating the prises the core of from the kernel. In the meantime, we tests had seemed too big, which was Linux development can look forward to a gradual depreca- why the person had only these few tion process, and a search for user apps smaller tests to satisfy their curiosity. activities. Traffic vol- that depend upon it. umes are immense, An interesting and ironic result of all DeLOCK USB Ethernet often reaching ten this attention being given to sysctl is that Arnd Bergmann posted a patch to sup- thousand messages the code is actually improving, error port the DeLOCK USB Ethernet adapter. in a given week, and messages are becoming enhanced, and David Brownell signed off on the patch, keeping up to date so on, as the whole thing gets closer to and after some discussion of how best to with the entire scope of development being removed entirely. submit it, Arnd and David sent it along is a virtually impossible task for one to Greg Kroah-Hartman to be included in person. One of the few brave souls to Maintainership Issues Greg’s regular USB updates. The patch take on this task is Zack Brown. Pierre Ossman has submitted a patch may have some problems, and on some Our regular monthly column keeps marking himself as the Multimedia Card hardware, it’s been shown to lose pack- you abreast of the latest discussions subsystem maintainer, since Russell King ets. This could be a case of broken hard- and decisions, selected and summa- stepped down as maintainer and marked ware – it’s too soon to tell. Regardless, rized by Zack. Zack has been publish- the driver as orphaned. Pierre has also the patch seems good enough to perco- ing a weekly online digest, the Kernel taken the liberty of renaming the driver late up toward the official tree, where Traffic newsletter for over five years “multimedia card and secure digital sub- hopefully it will get further testing. now. Even reading Kernel Traffic alone system.” One reason a patch can be accepted can be a time consuming task. Jiri Slaby has added an entry to the like this when there is an issue of poten- Linux Magazine now provides you MAINTAINERS file, for the Moxa tial data corruption (or at least slow- with the quintessence of Linux Kernel SmartIO/ IndustIO serial card driver, and down), is because this sort of driver activities, straight from the horse’s named himself as the maintainer. He has code is very self-contained; even if there mouth. also added an entry for the Multitech is data loss, it would be extremely un- 14 ISSUE 74 JANUARY 2007 Advertisement likely to affect any other part pages channel of the same of the kernel. And presum- IRC server. This seems to be a ably users trying out such a much less populous channel, new driver would understand with only about ten partici- that they are testing some- pants. The ‘huge pages’ Wiki thing that may not be quite also seems to have been ready. fairly quiet lately, while the filesystem Wiki is apparently Usbmon Interface updated frequently. Paolo Abeni has written a bi- In the same vein as these, nary interface into usbmon, Darren Hart has announced a via a DebugFS directory new ‘realtime’ wiki at http:// entry. Paolo also added an rt. wiki. kernel. org, maintained ioctl() call to allow resizing by himself and Theodore the amount of USB data Ts’o. It’s possible that wiki. stored in each DebugFS re- kernel.org will host any num- cord. Pavel Machek has asked ber of wikis. Anyone inter- if this meant we’d be taking ested in hosting a kernel- out the existing text interface; related wiki there should ask and Pete Zaitcev explained the site administrators for that the text interface would help. As Ted points out, continue to be supported, maintaining a wiki can be a at least until a simple com- lot of work, and you should mand-line tool had been try to arrange to have at least written to interact with the a couple of people to act as binary interface. editors, maintaining and grooming the site over the Filesystems Wikis long term. Valerie Henson has an- nounced a new filesystem Generic Backlight Wiki at http:// linuxfs. pbwiki. Holger Macht has written a com and a new IRC filesystem patch to support a generic discussion on the #linuxfs backlight interface in the channel at irc.oftc.net. At the ACPI driver, controllable via time of this writing, a few /sys/ class/ backlight. For dozen folks are on that chan- backward compatibility’s nel. sake, he’s also kept support Valerie has also created a for the control machanisms ‘huge pages’ wiki at http:// in /proc. Pavel Machek, for linux-mm. org/ HugePages one, likes the code, and said along with a corresponding it should be incorporated into IRC discussion on the #huge- the official kernel tree. Figure 1: linuxfs is a new filesystem wiki for Open Source developers..
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