JFS May Make It Into 2.4
Grimsaado writes: "LinuxWorld has an article on IBM's JFS and how it might be included in 2.4 as well as some technical fluff on it's phenominal cosmic power." Heck, with the number of journaling file systems, it's like being at a file system buffet at this point.
If Linus has a problem with ReiserFS, it is that he probably fears some of the exciting new ``disruptive'' concepts that Hans Reiser has planned. ReiserFS is truly innovative. For those interested in the innovations, there is a White Paper available. I'm sure that Hans Reiser's roadmap is what is scaring Linus. I'll be happy to see JFS make it into 2.4, but ResierFS deserves to be there too. I urge anyone with a slight interest to try out ReiserFS. I'm sure you'll agree then that it deserves a place at the table. I'm a late adaptor, and skeptical of new code (I used Xia FS for years after ext2 was available). If conservative old me can handle ReiserFS, anyone can.
-dB
"It if was easy to do, we'd find someone cheaper than you to do it."
Well, IBM's "JFS for Linux" is based on their port of JFS for OS/2 (remember that?) as opposed to their JFS for AIX, which is what most people associate with the name.
The current JFS for Linux project is, for instance, still case insensitive. Hardly an acceptable situation for a UNIX filesystem, but hopefully one that can be fixed.
Theres more about this thing at http://www-4.ibm.com/so ftw are/developer/library/jfs.html. One irritating thing about it is that theres no support for floppy disks, or other small removable media. Understandable considering the system, but floppy disks are still quite handy. (Assuming the page I was reading is up-to-date)
http://twitter.com/onion2k
Sure, let's just piss in Hans Reiser's petunias. A lot of people I've talked to seem to thing that Reiserfs is the farthest along journaling filesystem and I'm sure including some other journaling filesystem in 2.4 would be a major poke in the eye for him.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
The current 2.4.0-test kernel is getting very close, and Linus now appears to be only accepting bug-fixes and the odd self-contained driver. There is no way such fundamental changes could go in now.
None of which can read/write BFS at this point, despite the fact that it's well documented in Practical File System Design with the Be File System by Dominic Giampaolo.
Grumble grumble complain complain...
Well, what can you do about setting up a database for us with your Java experience?
[Dead silence]
The biggest problem with Java is not with Java itself; it's with the naïve software engineers who only want to do "neato-cool" things with it. This makes Java engineers look more like effeminate interior designers.
Another problem with Java is its inherent latency. Java servlets perform, on average,at one fourth the speed of a comparable perl or ASP database. For instance, Winamp's entire server is run on Java servlets. It currently runs half as fast as Slashdot (which we already know, is kinda slow already). Add AOL's outdated unix server, a slow client computer, and an even slower connection, and you've got a really bad experience on the client side."Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
whose webmasters don't understand that there are vastly superior ways of building websites.
Really, Java has its uses, but JSP has got to be the most fractured and counterintuitive technology I have ever come across. Even on the most ra-ra Java websites, you can easily find serious critics of JSP.
Compare JSP to PHP generated pages for any application - there's no comparison with regards to simplicity, speed, and suitability.
Hell, even mod_perl is preferrable.
Well, first of all, people routinely use ext2 with 45G or 60G drives (I have one), and it doesn't seem to be a problem. Furthermore, boot time can't be such a big issue for the kinds of customers IBM is targetting because many of IBM's AIX machines used to take from minutes to hours (!) on every boot just to get their SCSI subsystems up (I hope they have improve this by now); in comparison, the time for any fsck is negligible.
But most importantly, just because JFS spreads out the time for maintaining file system accesses doesn't mean you aren't paying for the time. Each day, the transactioning that JFS may cost you a few hours in computer time, compared to a system that doesn't do transactioning. And with JFS you pay that cost whether your system crashes or not. In fact, the more reliable your hardware is, the higher the cost of JFS.
So, would you rather lose a few hours of computer time every day, or lose a few hours of computer time on the very rare occasion that the machine was not shut down properly?
"Cool" maybe, but not very useful. Or are you in the habit of leaving most of your disk unpartitioned so that you can eventually grow into it? Last I used it, LVM/JFS couldn't even shrink file systems.
I think the popularity of JFS/LVM on AIX is rooted in particular idiosyncracies of IBM culture and limitations of the AIX operating system. On Linux, easy backup/restore, GNU parted, fast fsck, and fast boots give you more flexibility than LVM and JFS, with less runtime overhead and less complexity.
Scramdisk is currently being ported from Windows 95/98/ME & NT/W2k to Linux (by myself and AJ). This will allow the creation of a "virtual container" that can contain any filesystem - including filesystems that implement journaling.
"Mary had a crypto key, she kept it in escrow, and everything that Mary said, the Feds were sure to know."
BUT this is good! This is called progress, and this is called competition. File systems may seem moot, but I'm glad people haven't given up. Who better to poke the fire than IBM?
I think the future holds many things in file storage (perhaps we'll be using XML for data structure), and the more I hear about the basics of storage, the better I think computers will become.
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Nope. Journaling File System. Another in a series of a series of a series of a series of a (thwack) of a series of journaling file systems due to make it into the linux kernel.
Others include (from memory)
ext3
xfs from SGI
ReiserFS
I think there are others, but I can't remember.
-- IANAEG - I am not an elder god.
The page is still slashdotted. In the JFS for Linux-FAQ's it says "We were able to get JFS on 2.5 list of items to be merged....", however, the JFS core team wants to wait until an alpha version is ready (a beta version is excpected ro be released this month) before any real attempts to make the JFS part of the (standard) kernel are made.
I had seen a demo of XFS and JFS about 6 months ago. At this time I was already using ReiserFS. At that point XFS and JFS in my opinion had a very long way to go especially XFS. ReiserFS has seemed to be stable for quite some time now I have been used it on production machines without a problem. It has also been included in some distros like Mandrake 7.0. This seems to be a proven product in my eyes. I would hate to see a good product passed up because there is political or commercial (insert IBM logo) motivation. Also not to leave out ext3, I have not used this but here that it is also very mature at this point. I know some commercial companies are using it for their SANS such as VA. They have been using a modified version of ext3 for thier SANS for at least 6 months now. Also seems proven.
Tough I'm not a specialist at all, I read an interesting article on it at Linuxgazette . Interesting technical information (datastructures etc...)
By the way, I got the link in a comment here at slashdot (some time ago).
Ahhh...the great dumpster continuum. Many a free computer will be found there. -- sowth (748135)
Actually, he heard right ;-).
You see, while JFS is available for OS/2 Warp Server for e-Buisness (Aurora, Warp 5 Server), it's not available for the workstation version of OS/2, OS/2 Warp 4.5 (Merlin with the kernel update fixpack).
So a project was put together to take the GPLed JFS code and get it to run on OS/2 4.5.
Steven E. Ehrbar
> Not allowed to.
Huh? Learn how to join the kernel mailing list
Been there. Done that. All of the decisions are actually made off-list. The list is a decoy.
> And then ignore your patches.
Hmmm, maybe that says something about the quality of your coding... (i.e. it sucks ass)
And who are you, exactly? Some expert in ass-sucking? Getting patches and ideas rejected by The Posse (Viro, Cox, Tso, Molnar, etc) doesn't mean they're bad. To date, it's meant that they tickle an ideological allergy to things not posix. For instance, even though Linus stated he wanted a clean way to suppor streams in Linux, in order to support existing filesystems, The Posse wouldn't let it happen, and even went out of their way to stifle the debate. Ask Cox about his kill file sometime. He won't even include fixes to printk to provide 64-bit support (in spite of the fact that linux is supposed to run on 64-bit machines, like UltraSparcs).
Just because they're the current in-crowd dosn't make them right. For instance, Linus refuses to let a kernel debugger be included in Linux. He, and a number of morons on the kernel list, say that printk is all you need to debug the kernel. Yeah, okay. But then support for printing 64 bit numbers in printk is rejected, meaning that it's actually impossible to debug 64-but data structures with the recommended method, printk. It's all sort of silly. I can't wait to see 2.4.0-pooch-screw-37.
I can understand that Linux doesn't have a design, that's it's evolved as it's coded. But it could at least have a philosophy. Currently (2.4.x) it just has problems, and the Mindcraft benchmarks to refer to.
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Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
I'm LOSING karma with this one, not gaining it. I do need some deficit, otherwise I'll make an Icarian flight.
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
As previously stated JFS is released under GPL.
AIX's JFS contains licensed code from outside sources. Several years ago, JFS was redesigned from the ground up for OS/2 Warp Server. This version does not contain any encumbered code and was designed to be more scalable than AIX's version. This JFS first shipped last year with Warp Server for e-Business.
Therefore, the Linux offering of JFS is not the same filesystem you'll find on AIX, and you won't be able to share a JFS file system between AIX and Linux. (You will be able to share one between Linux and Warp Server.)
The 1/4 figure comes from the servlets at www.winamp.com taking 10 seconds to load, as opposed to the Slashdot perl scripts taking 2.5 seconds to execute.
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
Thats my biggest fs problem at the moment. The average home user can go make a cup of coffee while the machine fscks after a crash. Even our departmental server doesnt take that long. But just about the only time I've ever had to restore stuff from backups is when people have done
.tex
rm *
or similar. I do all this backup nonsense just to protect themselves against their own stupidity?
So, are any of the journalling FSs smart enough to rollback a journalled transaction to undelete a file? And provide user-level tools to do it?
I know there is the beginnings of undelete support in ext2 FSs, but its all very beta. Surely when designing a new FS you'd factor it in from the start...
Baz
Yeah, they'll add it by "accident" like with JFFS.
Hi, we're happy to announce the release of kernel 2.4.0-pooch-screw, wherein we screwed up the VM and VFS again, and occasionally even Ext2 gets scragged, but we tossed in another journaling filesystem.
Perhaps these guys are smoking cherry-flavored crack. What's the kernel list have to say about this? Viro? Care to chime in? so they're working with "the community" to get it included, in spite of the fact that the thrid feature freeze is on?
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Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
Heck, with the number of journaling file systems, it's like being at a file system buffet at this point.
Mmmmm.. all you can eat inodes.
If /. did mirror sites, then that could take ad revenue away from the said site. There is also copyright issues.
The basic sleazeware produced in a drunken fury by a bunch of UCBerkeley grad students was still the core of BIND. --PV
This causes filesystem checking software (like fsck) to work dramatically faster.
fsck does not go faster; it is simply not needed. The file system guarantees that it will always have its integrity intact. Therefore there is no cleaning up to do after an unclean shutdown.
There are still fsck programs for journaled file systems, though - they might be useful for example after being hit by a bug in the file system itself.
--
Bingo!
This came up months ago on the kernel list - simply the weekly summary, even.
Journalling requires changes in the VFS. Rather patch the VFS many times for each member of the 'buffet' of journalling filesystems becoming available, Linus said he'd prefer to find the common elements, and make VFS "journalling-ready".
The individual journalling filesystems would have to work with the new VFS to make sure it was suitably changed, and to make sure their code would work with it.
This sounds like the correct approach to me, even if it does delay things a bet. Better than letting ad-hoc adaptations creep into the kernel.
The living have better things to do than to continue hating the dead.
This workstation software not only includes JFS, IBM Desktop on Call (remote control software), Star Office and Lotus Smart Suite .. but the same SMP which is in Warp Server for e-business is also available as an option.
Not too shabby.
Regards,
Bob St.John
Does eComStation (eCommStation?) have a market beyond OS/2 upgrades?
All I hear about it is a (sort of) upgrade from OS/2 Warp 4. But it could be because I am not in the circuit of huge parks of company computers.
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Men with no respect for life must never be allowed to control the ultimate instruments of death.
GW Bu
Hmm .. is Scramdisk Linux opensource then? I use e4m since the source is available. I never use any crypto products where the source hasn't been submitted to open peer review ..
it's in my head
Revelation Zero: The beginning of the end.
As any yacht captain will tell you, you'll never lead the pack with a full load of bilgewater. The same is true in programming languages: if you don't get down-and-dirty with the low-level, the end result is guaranteed to be inefficient. This is why the naïve Java programmers can never build anything low-lag with a JDK.
Okay, reality check time: Java is at the bottom of the database barrel as far as performance and reliability go. Just see winamp.com's database structure (that is, if the site is running at all!). They use Java servlets. The average latency for a query on a 60K/sec connection is 10250ms; four times as slow as PHP, ASP, and Perl.
My suggestion to you is to take those blinders off, stop trying to say "Sun Solaris 7!" with the effeminate lisp, and start learning some worthwhile database APIs.
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
Someone has changed RedHat 7.0 to allow you to install ReiserFS during boot.
http://cambuca.ldhs.cetuc.puc-rio.br
So, for anything that is critical or costly, you need redundant hardware and replication anyway. Once you have that, you are already protected against downtime from running an fsck should the need ever arise. There is no need to slow down your (replicated) systems additionally with JFS for a very marginal benefit.
Fsck on ext2 is pretty fast, crashes are very rare for server systems, and servers require regular backups anyway. It is more rational to run integrity checks in batch mode when necessary than to pay overhead on every file system access to deal with the possibility that the machine might crash at any moment. I think JFS (and its companion, LVM) are simply not good engineering tradeoffs for most (all?) applications.
It seems these days that everything is getting into the Linux kernel. While this is great, I imagine there are going to be some newbiew that are thinking which should I choose, which is better. The answer is more of what are your needs.
I wonder how distros are going to handle this. If a distro includes only support for one, then a user will have to choose the distro based on the fs he wants, if they include all the user then has to choose which one he wants to use.
Since this is compiled into the kernel can you use more than one journaling file sytem at a time?
Can I have one partition using ext3fs, one using reiser, and one using IBM's jfs, and one using XFS? Not that I'd want to though.
I don't want a lot, I just want it all!
Flame away, I have a hose!
Only 'flamers' flame!
I heard that somebody was re-porting it to OS/2. How is it going?
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Men with no respect for life must never be allowed to control the ultimate instruments of death.
GW Bu
I gave you a good example, isn't that enough? Go get the stopwatch and start browsing!
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
If you think that the 2.4 kernel is 'long overdue' then why don't you volunteer and help out the effort?
Not allowed to.
They get to tell you to fix your problem yourself.
And then ignore your patches.
________________________________________
Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
Actually, Linux 7.0 has been out for a while - I dunno why it was big news last week.
:)
--
"Hey, the last 9 months I programmed on this superduper filesystem and it will be great for the next Linux Kernel!"
"Erm.. yeah, great but the VFS layer isn't up to par so we can't use your functionality in the rest of the system anyway"
Besides that... Linus isn't stupid. He already mentioned a zillion times he wants to end the featurecreep and finish the kernel. Now adding another filesystem will definitely delay the kernel's release BECAUSE of featurecreep, something Linus wants to avoid.
But.. with a better design of the system internals, this wouldn't have to be necessary: IBM would just add another module and everything would have been fine. ah well...
Good old.. mr. Tanenbaum ;)
--
Never underestimate the relief of true separation of Religion and State.
as far as I have read on kernel threads (http://kt.linuxcare.com) there will be no journalling systems in 2.4, initially at least.
This is kind of an odd announcement especially with the kernel in its current 'slushy' state.. I am guessing that 2.4.X with X>5 before the first journalling systems begin to appear.
The latest drops however have implemented the case sensitive mode and made it the default.
For those interested the you can get on the jfs-discussion mailing list by sending email to Majordom@oss.software.ibm.com with the following command in the body of your email message:
Information on IBM's OSS projects can be obtained from http://oss.software.ibm.c om/ developerworks/opensource/And as far as the "buffet" of Filesystems goes: choice is always good, lots of choices even better.
Post anonymously - For when your opinion embarrasses even you!
- The current JFS for Linux project is, for instance, still case insensitive. Hardly an acceptable situation for a UNIX filesystem, but
hopefully one that can be fixed.
actually, if you'd go look, you'd see that as of release 13 of JFS (September 29, 2000) is now case sensitive. But I suppose you can't be bothered to research something before you flame about it.Having been a contractor at IBM in Austin, and having spolen personally with some of the AIX developers and their managers, I can state that IBM groks open source. (at least the departments I've had contact with did) IBM's JFS may not be the most mature journalling filesystem for linux out there, they aren't claiming to be, but it is another one. When it's all done, we'll probably have a couple of jfs's left (one that only journals meta-data, and one that journals both data and meta-data) and they'll likely have incorporated the best pieces of the jfs's that have fallen aside. Isn't that what it's all about? So all you people who spread doom and gloom about IBM and open source, just stop it. We're sick of it ok?? What about Sun?? They've pissed on the open source community and yet what of them? Oh, that's right... they're not IBM. Evil big blue brother IBM. get off your high horses and accept that they're doing something good for you.
"We are not tolerant people. We prefer drastically effective solutions"
The article states that case sensitivity has yet to be implemented. I'm not sure I understand...
... and AIX's JFS is already case sensitive, so what's changed?
I would have thought that case insensitivity would be the sort of thing you have to put effort into developing -- and that case sensitivity is something that "just happens"?
Can anyone explain what I'm missing?
--
(When I log out of my machine, I want to _know_ that the contents on it can be reached by myself only - no matter what any repairman, hacker or ... police, does)
it's in my head
Interesting. I was able to get the page without problem. In case you don't get the chance, JFS stands for Journeled File System.
Simply put, Journeling File Systems keep track of where data is placed on a file system. Whenever you move files, add or remove files, etc., the file system knows where those files go (by writing to a "journel").
The good thing about this is that when a computer goes down, the filesystem can use the journel to put things back in order. Otherwise, it must go through sector by sector and find the data that it has "lost". This causes filesystem checking software (like fsck) to work dramatically faster.
The bad thing about this is that these types of file systems can take a performance hit if a lot of disk IO goes on. I hope you get a chance to read the article, as it addresses some of these issues.
--Mando
This is like the promise of that RedHat boss who claimed last year or the beginning of this that 2.4 is going to be released in march 2000...
Linus just isn't going to let those journalled filesystems in until the VFS layer has been worked out so that the different fs's can share functionality instead of doing everything on their own.
Isn't Open Source wonderful?
Native S/390 support and a journaled file system. I think we are seeing the beginnings of a new breed of Linux.
Well, duh, that's what tracert and telnet are for!
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
Then why don't you just do a tracert to winamp.com and slashdot.org and subtract the ping times from the total time? You did graduate from elementary school, didn't you?
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
He says the editor may have just emptied the disk file prior to writing the new data. If it crashed in between, the journalled data would have been correctly empty. Nothing any journal file system can do about that, unless it also includes version control in some form.
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Infuriate left and right