Guest post by Computer world points out five major new features , you might have missed out in the recent 2.6.27 release. These include briefly, better wireless and webcam support, UBIFS filesytem for embedded devices, Ext4 filesystem with better performance and scalability and increased support for network devices as well.
is it considered stable, or experimental?
According to Wikipedia,
AFAIK, ext4 will be included in Fedora 10 – but only if you manually enable it during boot.
In short – stable enough for testing; no stable enough for production.
– Gilboa
I believe its already included in F9 but like you said, you have to specify you want it. Not available by default.
I believe the support was dropped just before F9 release. (Though I’m not sure)
$ locate ext3.ko
/lib/modules/2.6.25.14-108.fc9.x86_64/kernel/fs/ext3/ext3.ko
/lib/modules/2.6.26.3-29.fc9.x86_64/kernel/fs/ext3/ext3.ko
/lib/modules/2.6.26.5-45.fc9.x86_64/kernel/fs/ext3/ext3.ko
$ locate ext4.ko
$
EDIT: I stand corrected.
$ cat /boot/config-2.6.26.5-45.fc9.x86_64 | grep EXT4
CONFIG_EXT4DEV_FS=m
CONFIG_EXT4DEV_FS_XATTR=y
CONFIG_EXT4DEV_FS_POSIX_ACL=y
CONFIG_EXT4DEV_FS_SECURITY=y
$ locate ext4dev.ko
/lib/modules/2.6.25.14-108.fc9.x86_64/kernel/fs/ext4/ext4dev.ko
/lib/modules/2.6.26.3-29.fc9.x86_64/kernel/fs/ext4/ext4dev.ko
/lib/modules/2.6.26.5-45.fc9.x86_64/kernel/fs/ext4/ext4dev.ko
– Gilboa
Edited 2008-10-18 11:49 UTC
The “dev” designator has been removed from “ext4dev” in this release. ext4 will likely be cleared for general use sometime soon.
From TFA:
So… has jffs2 been a figment of my imagination these last 7 years… from kernel 2.4.10 up?
And why is he lumping all USB interfaced drives together are flash?
Edited 2008-10-18 11:13 UTC
if you follow the link in the article, you come to this:
http://lwn.net/Articles/276025/
among other things it the limitations of jffs2.
still, neither seems to be aimed at usb thumbdrives or removable cards, they are supposed to be used for internal flash on phones or similar.
Edited 2008-10-18 11:28 UTC
He actually got that part right by referring to the fact that most flash storage today has a built-in FTL. But he obviously has not read his own LWN link or he would know that this is more or less a hand off from the venerable jffs2 to ubifs, and that Linux is not getting MTD support for the first time, as he strongly implies. For those who might not be familiar, jffs2 can be slow to mount on large flash drives today, which would have been unthinkably huge drives back in 2001 when it went into the kernel. It is really only recently that it has started to show its age. I’ve never had a device with enough raw flash for jffs2’s limitations to be noticeable.
OLPC uses JFFS2 and has run into some of the limitations especially the delay in mounting is pretty significant.
UBIFS is being considered by the group.
http://lists.laptop.org/pipermail/devel/2007-December/008348.html
Before this fs was merged, OLPC and N810 were the two devices that Nokia tested it on. When David Woodhouse from Red Hat wrote JFSS2 originally, it wasn’t really meant to handle these sort of devices. UBIFS (and LogFS as well hopefully) is a pretty welcome improvement.
Indeed, jffs2 has reached EOL. Flash partitions, today, are huge. It was only the “Linux now supports flash” contention on Stephen’s part that riled me regarding the original article.
I was rooting for the very ill-named LogFS. UbiFS appeared out of the blue, so to speak.
Meritocracy. Whichever of the two is better performed and/or most stable.
Open source code progress is, in some ways, not unlike evolution. You have “survival of the fittest” (as this example of LogFS and UbiFS illustrates) and you also have “inheritance of characteristics” in the sense that now that UbiFS code has been chose to include in the kernel over LogFS, the the UbiFS code will be passed on to subsequent improvements while the LogFS code will not.
This one surprised me a bit. I assumed that LogFS was the successor to jffs2… and had never heard of ubifs. (I did have some complaints about logfs’ name, though. And jffs2’s, too.) If ubifs got through the LKML review process that’s certainly cool with me. I’m just not used to being caught with my pants down so.
Edited 2008-10-20 01:46 UTC
what DOES it mean anyway? Logarithmic filesystem? Logging filesystem? Logical filesystem? What?
jffs2 stands for journalling flash filesystem 2. Which is a bit odd because it is a log-based filesystem and not a journalling one. The name “logfs” was a joke in return to jffs2’s name. Logfs is not a log-based filesystem. It is a journalling one. The LogFS people say they are contributing to a tradition. I feel that confusion is a tradition that we could all do with less of.
Edited 2008-10-20 13:35 UTC
In-jokes never get old, do they?
Maybe that’s because they’re never funny to begin with.
You are partially correct but LogFS is currently a log structured filesystem and does scale logarithmically for the most part, so the name actually fits. Oh, btw they are open to suggestions for new names as well. Can’t get better than that!
If the landscape has changed, they need to change their FAQ:
“””
The name LogFS was chosen for several reasons:
JFFS2, the Journaling flash filesystem 2 is actually a log-structured filesystem. LogFS is a journaling filesystem, so its name has to hide this fact to continue a tradition.
“””
Edited 2008-10-20 18:25 UTC
If you are going to refer to a FAQ, you are better off providing a link. Blind references make discussions difficult. Also you might as well as read the subsequent lines at
http://www.logfs.org/logfs/
“During development, LogFS actually turned out to be log-structured as well..”
If that is true I will, of course, rest the case. Perhaps my information was out of date. It does make sense for a flash-based FS to gravitate toward log-centricity. Damned odd for them to make such a drastic change, though. I’m not quite sure I believe it.
Edited 2008-10-20 18:38 UTC
I am using that kernel with Intrepid Ibex. I haven’t had any problems. My USB camera finally works. That is the first thing I noticed. Everything else seems to work well as usual. I would like to convert my external Firewire drives to ext4 to see how it performs.
The latest version of Mandriva uses 2.6.27 by default. The wireless for my laptop (Atheros AR5007eg) works “right out of the box” and my laptop’s webcam works quite nicely, too.