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A Short History of Btrfs
diegocgteleline.es writes "Valerie Aurora, a Linux file system developer and ex-ZFS designer, has posted an article with great insight on how Btrfs, the file system that will replace Ext4, was created and how it works. Quoting: 'When it comes to file systems, it's hard to tell truth from rumor from vile slander: the code is so complex, the personalities are so exaggerated, and the users are so angry when they lose their data. You can't even settle things with a battle of the benchmarks: file system workloads vary so wildly that you can make a plausible argument for why any benchmark is either totally irrelevant or crucially important. ... we'll take a behind-the-scenes look at the design and development of Btrfs on many levels — technical, political, personal — and trace it from its origins at a workshop to its current position as Linus's root file system.'"
This looks like a promising filesystem - as ZFS on linux is, at present, doomed to die an ugly death, btrfs looks to address a lot of the shortcomings of other filesystems and bring a clean, modern fs to linux. It goes beyond ZFS in some areas too, such as being able to efficiently shrink a filesystem, and keeps a lot of the cool things that ZFS made popular, such as Copy-On-Write.
It looks like Btrfs also addresses some decisions that were made with the direction that ZFS would be going in, or how it would handle certain problems that now with hindsight behind the developers, they possibly would have done things differently.
Apple are really struggling with ZFS, with it being announced as a feature in early betas of both Leopard (10.5) and Snow Leopard (10.6), as well as being there in a very limited form in Tiger (10.4) - maybe development on Btrfs will leapfrog ZFS for consumer-grade hardware and Apple can finally look at deprecating HFS.
Specialist Mac support for creative pros, Melbourne
Is this ever going to replace ext4? The ext series of file systems are 'good enough' for most people, so unless it has some epic benchmarks I can't imagine a huge rush to reformat. Maybe that's what drives file system programmers insane. The knowledge that for the most part, it's going nowhere. FAT12 is still in use, for Christ's sake.
No, it's not - but you're wrong. :"Linus's" is correct. The 's' after the apostrophe only gets dropped in plurals.
Will you also be enjoying your media in REAL PLAYER?
It's not that hard!
Not necessarily true: http://www.bartleby.com/141/strunk.html#1
It's fine to drop the 2nd s, at least in British english. Though, there doesn't seem to be any hard and fast rule..
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
Both are correct, depending on who you ask. It's a British English vs. American English thing. Up here in Canada, just the apostrophe seems to be the preferred form.
upon the advice of my lawyer, i have no sig at this time
Is it Beta? The fact that Linus runs it as his root fs doesn't tell me much. Now, if you told me that's what he uses for ~/, I would be more impressed.
The important question to me is, how long 'til it gets in the major distributions?
Help! I'm a slashdot refugee.
I was taught in my American schools (grade school, even) that you drop the second S on names that end in S. "Linus'"is how I was taught.
There doesn't seem to be any hard and fast rules about anything in British english! ;-)
In Fowler's Modern English Usage, which is generally considered to be the bible of english usage by UK journalists and writers, there's an article called "Possessive Puzzles". In that, he says it was "formerly customary" to drop the last 's', but not any more.
If it was formerly customary in Fowler's day, i reckon it must be well and truly archaic now.
That's interesting. I think in Britain the preferred form of anything is to put an apostrophe anywhere it can possibly be put and drop any syllables that can possibly be dropped.
It seems the version with the final 's' is more modern than the version without it. Considering their efforts to update the language, it's perhaps not entirely surprising that the Americans prefer the more modern form.
Yeah, that's what Fowler reckons, too.
That argument isn't actually based on the technical merits, and thus doesn't make any sense..
Just because a Real OS features a Real FS backed up by a real company, doesn't necessarily mean the FS or OS are any good on technical merits compared to a REAL project licensed under a REAL free software license backed up by a REAL community and supported by a REAL foundation.
gor blimey guvnor you aint arf stereotypin us brits'.
I've lost files on lots of different systems, including NTFS and ext3 and the kitchen sink. It's rarely the fault of the filesystem itself.
That this is a "service" provided by LWN so that non-subscribers can read premium content; this story would be free for all come Thursday, but apparently "diegocgteleline.es" didn't feel compelled to mention that, that LWN's weekly page is premium content, and that premium content subscribers help LWN stay afloat -- when it's almost gone under a couple times.
With the COW-enabled b-tree storing everything including metadata and packing it in the same block as the data it describes, the atructure looks quite similar to reiserfs (v3) in terms of error tolerance and recovery. Should this get a tool like the reiserfsck --rebuild-tree, I'm switching - this single feature (well, and some quite sensible performance) is keeping reiserfs on my systems. Saved me a lot of grief several times, when an ext filesystem would be a totally lost cause (or lots of $$$ for a data recovery company), without any built-in utilities, and really no way to write them, that search the entire disk for anything that looks like filesystem metadata and try to make sense of it, even with all superblock structure completely missing and the rest spotted with garbage.
This is Slashdot. Common sense is futile. You will be modded down.
I asked when it would be usable for "people who backed up their data" about a year ago -- which is about how long I've been using it -- and the answer was, "No firm date." If you load up a 2.6.31 kernel, the commits have reached the point where not only shouldn't you see significant on-disk format changes, but that the bulk of non-RAID tweaking to occur is probably performance related. (RAID is coming, but it's only just started.) Grub still doesn't know about btrfs, and that's semi-back-burnered functionality, so in order to get it to boot, you need a /boot partition on something Grub does know about.
The fact that Linus runs it as his root fs doesn't tell me much. Now, if you told me that's what he uses for ~/, I would be more impressed.
It gets even worse. FTFA:
Linus Torvalds is using it as his root file system on one of his laptops.
Maybe one of his spares?
I'm speculating, but note that the article doesn't say "his main laptop", which it could, and which would be a better "seal of approval", so it probably would if it was true...
As if fsck wasn't bad enough to use in business talks, now I have to get prepared for btrfsck
You can't even settle things with a battle of the benchmarks: file system workloads vary so wildly that you can make a plausible argument for why any benchmark is either totally irrelevant or crucially important.
As pointed out, filesystem workloads vary massively, which is why it's good to have a choice of different filesystems which can be chosen based on individual requirements. Only offering a single filesystem like many other OS's do is extremely inefficient. One size does not fit all.
http://spamdecoy.net - free throwaway anonymous email - avoid spam!
That argument isn't actually based on the technical merits, and thus doesn't make any sense..
So what's your point? that ext4 is better than ZFS on technical merits!?
I doubt it, but he will have to hand over REAL MONEY using nothing but REAL WHEEL BARROWS.
Allow me, if I may, to open the can of worms here.
Why is it that in 2009 we can't get a filesystem that allows easy undeletion? It all happened to us one time or another: You typed that 'rm' command you shouldn't have, and now your work of the past few hours is gone. If only there was a simple way to undelete those few recent removed files...
We all know that the data is not zeroed on deletion, so why can't we have a File System that (preferably after fs umount) can scan the blocks and retrieve any file whose data blocks have not been overwritten yet, even if it takes a lengthy whole disk surface scan.
Hell, in 1989, I could do just what I described above very easily on the Amiga (granted, it was floppy based, but still...), and I never lost a single file apart from disk errors. I can even do that fairly easily with external tools on NTFS. So Why are all the UNIX filesystems I know (and btrfs is apparently not going to be an exception) such a pain in the butt for undeletion?
Looks like these truths are not so self-evident after all...
Maybe someday you'll be a Real Boy
I wish the parent hadn't been modded down. He makes a point that should be addressed.
I've lost data on every file system that I've ever used, including NTFS, and the highly touted ReiserFS. Nothing guarantees the security of your data. The nearest you can come to data security, is to backup, backup, and backup again. Those people and organizations that keep regular backups seldom lose data. However, even those people can lose data in the event of a physical disaster (fire, flood, theft, being hit by a humongous meteorite) which is why off-site backups are important.
That said - IMHO, a journaling file system is an important first step to data security. NTFS and Ext3 are about equal, in my experience. Turning off caching features is an important second step. A power outage before data is written to disk, and/or while data is being written results in corruption in all current file systems. The important thing is, if data is mission critical, you want it written IMMEDIATELY, not floating around in RAM.
And, finally, you NEED redundant backups. Anyone who fails to make backups WILL LOSE data, eventually.
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
It's my layman opinion that undeletion doesn't belong to the filesystem, but to userspace ; kde and gnome already provide an undelete wastebasket. It is even conceivable on some systems to forbid users from truly deleting files (think White House staff, for instance). And you already can alias rm * to 'mv * ~/wastebasket/' for your regular users.
But what you are really asking for is a magical shield for your mistakes as root. Either write yourself a false rm script as you would for normal users, or pay attention. But really, you shouldn't delete anything as root unless you've tested by moving away what you intend to delete that the system is working without this specific file you want to erase. Only after testing, delete to your heart content.
Who cares? In a few years' time, this will be obsoleted by its successor, icantbelieveitsnotbtrfs.
Everybody can make a typo without being stupid. I'd rather sum up my words by "don't be careless, problem solved".
Can i have a copy of that book ?
Slipping shoelaces ?
Except that English is defined by how it's used not by some arbitrary authority, in spite of what those boys up at Oxford will tell you. The fact that people use both "Linus's" and "Linus'" means that both are acceptable. By the same token, "ain't" and "y'all" are now recognized words because people use them and nobody is confused by meaning. "Google" is now a verb, as well.
If I say something in what I believe is English and you understand it unambiguously as English, then it's English or an accepted dialect.
The road to tyranny has always been paved with claims of necessity.
I don't really like the name. The first time I look at the name, I thought it was short for "Bit Rot Filesystem".
In spoken English, you generally pronounce the second 's' (unless you are a pedant of some sort), so it would stand to reason that the second 's' should remain. There is another motivation: the "'s" is actually a clitic that attaches to phrases (usually noun phrases) and is thus a separate word, not a part of the word it is attached to. As such, it should always be spelled out (as it is always pronounced).
GPL licensed. Without it, companies like IBM and Red Hat would not be willing to put so much time and money into the platform. Just look at Apple. They went with BSD code and instead of simply building a new "distribution" of BSD, they forked it *AGAIN* and made something that is largely incompatible (sure you can run BSD apps on OS X, but you cannot run OS X apps on BSD, this is BY DESIGN). This kind of thing happens time and time again in the BSD world and is IMHO the primary reason why BSD has to date largely failed despite its technical advantages.
I'm sorry, but that is actually the best part of the arrangement.
If there were no BSD, Apple would not have thrown in the towel and used the Linux kernel. They would have gone the Microsoft route and created software that is completely proprietary. With the way things stand, Apple has created a platform that is relatively easy to port software to.
The BSD license has brought us amazing levels of compatibility in computing. Little thing called the network stack that I'm sure we're all happy was BSD licensed?
Long live the BSD license
No. I was alluding to GP's failure to make a good argument for supporting ZFS, using sound reasoning. I'm saying the truth of the premises doesn't imply the truth of the consequent.
ZFS on supported hardware is actually superior to ext4 on certain technical merits; primarily data integrity (checksumming), random write performance, and read performance (when massive amounts of RAM are available), and more advanced features (snapshots).
On the other hand, ext4 works on 32-bit processors (ZFS is only recommended to be used on 64-bit procs) with small amounts of RAM available, less than a GB; the minimum amount of RAM one should use ZFS with is 2gb, and 4gb or more is strongly recommended, above and beyond any RAM required by apps running on the machine.
But that has little to do with the OS being produced by a large corporation.
Offcourse , we need to implement a sort of timeout , to prevent locking the thread in case the first poster decides not to post.
No we don't, if it's locked and no-one is posting we won't get spam and people might actually read TFA.
Maybe you should get a REAL DOLL
“Common sense is not so common.” — Voltaire
http://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices
Except that English is defined by how it's used not by some arbitrary authority, in spite of what those boys up at Oxford will tell you.
Txt spkrs rejoiced. Thus started the revolution. Everyone left after the MegaWar was a freak, except for a small band of roving former English professors. These kept the language alive with campfire stories, in the vein of The Canterbury Tales, until one day, the world could rebuild . . ..
Hmmm, just keep meat products out of it so that it can be used in the Middle East without causing a religious problem and needs to be shut down once a week... ;)
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Ahhh, but, it seems that you have assumed AC to be human. ;-)
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
Wow. FUD flies fast and hard on slashdot. Zealots? Are you serious? Rather than mod your post as +1 Funny, I think I'll blow some karma and respond, just to set the record straight.
Laying aside misconceptions about the GPL, the main reason BtrFS is GPL is because it's part of the Linux kernel which is also GPL! How hard is it to grasp that? If Apple or anyone else wants to license Oracle's BtrFS code, they are welcome to negotiate and get the code under a different license than the GPL. It's that simple. BtrFS is an implementation of an idea, a specification. If Apple wants to write their own BtrFS driver, they are welcome to do that. Or Microsoft.
Why are developers who don't want their code to be ripped off (used without payment in a closed product) by companies and incorporated into a product are labeled zealots? How is this different than software companies requiring code to be licensed by third parties? So a company who creates some really cool technology that they license for a fee to others for use in products zealots? There really is no difference.
While I haven't written any software of note, I also use the GPLv2 (evaluating v3) since I want my software to be able to be freely used by those that want to use it, but if my code is that valuable to a company, I want to get paid for my trouble. If no one is willing to pay me, then that's fine. They are welcome to use my software without restriction, but if they redistribute it, to do so under the terms of the GPL. Guess that makes me a zealot.
But this goes to 11.
Alright, I'll bite some more:
The "don't be careless" position would be fine, but it's akin to never making any mistake, which, considering the amount of background cursing noise experienced in any IT profession, is the exception rather than the rule. If you've never been careless when working with computers then kudos to you, but I don't think that's the general rule. Oh, and I don't think I mentionned using rm as root (but of course, you want to be root to umount the filesystem and revent further writes after you realized your mistake).
For the sake of what follows, let's consider that I, stupidly or not, as a non root user, innadvertently deleted that 10 GB worth of irreplaceable data I just generated (eg that 10 GB HD video file of an UFO landing on my front lawn). This was my only copy. Now let's consider the options:
- 'rm' alias, a.k.a. as the Windows-like trashcan: That solution would be fine if I didn't (usually) want to have that file space freed straight away. If I remvove a 10 GB file from my system, I want 10 GB more disk space available => not the best option. Plus what if that file just got deleted from an UI (eg. the video editing app I was using under X) rather than from an 'rm' command. Also defuses the careless argument with "what if I am the most careful person in the world, but I am using an application (which I carefully picked), that has a bug, which noone foresaw, that deletes large files using system calls"
- snaphots: This looks like the best compromise at the moment, but for that to work, snapshots would need to occur in real time. I might be wrong, but I don't think this is the case on ZFS right now => if I recorded that UFO landing video and lost it in the interval between snapshots, it doesn't really solve my problem
- undelete in userspace through something different than aliases: I've seen this advocated again and again, and it is my layman's opinion that undeletion does indeed belongs to the filesystem rather than userspace. All undeletion takes is a chained list of blocks (so let's say 8 bytes for 64 bit block addressing of the partition, to be safe). Give me 8 bytes/block of file data, and I can now scan the whole partition, retrieve all data that has not been overwritten, and recover it. If I umounted my partition right after I realized my UFO video was deleted, it won't be much of a problem to recover it. Don't care much about filenames and perms as long as I can peek into recovered files (or parts of files), but if you insist, I'll be creative an flip a single bit instead of 64 for blocks that are sequential, so that I can use the remaining 63 bits, over multiple sequential blocks, for stuff like unique ID, original filename, perms, etc. Won't do much for small files, or if a lot of write operations have intervened in the meantime, but if that wasn't the case, there's a good chance you'll be able to rebuild it almost in full, even with a few missing blocks here and there
Now, I'll agree that not everybody wants to lose 8 bytes/block, but then mkfs could give undelete as an option on FS creation, and as long as people have a choice, everybody's happy...
Looks like these truths are not so self-evident after all...
I think you are not understanding me ; when I wrote "don't be careless", I meant in the light of my previous post, don't be a careless administrator. I understand your concerns, and I think strongly you're handling them backward. That's because you have, like most everyone, two hats and you are confused between when you have only your user hat on, and when you, as root, must treat your user double with a clue bat.
To follow on your video example, the main failure of it is : as a user, you want your 10GB disk real estate back. Dealing with disk space is not your problem as a user. That's when you put your root hat on, and become a BOFH against yourself. Not putting safeguards in this case, as an admin, is carelessness ; it means basically that you are servant to your users tyranny. Even as an admin, you should treat yourself with paranoia and don't fall into the almighty god power over everything trap.
That's when alias and scripts come handy, as a first line defense ; most of the time, removing a file to another location won't cause problem. After a certain delay, you, as root, can remove it for good. But you should stand firm to your own impetous, and, should you need 10GB on the spot, either tell yourself "nocando" or go buy a spare disk.
Elements of Style says:
Form the possessive singular of nouns with 's.
Follow this rule whatever the final consonant. Thus write,
Charles's friend
Burns's poems
the witch's malice
This is the usage of the United States Government Printing Office and of the Oxford University Press.
Exceptions are the possessives of ancient proper names in -es and -is, the possessive Jesus', and such forms as for conscience' sake, for righteousness' sake. But such forms as Achilles' heel, Moses' laws, Isis' temple are commonly replaced by
the heel of Achilles
the laws of Moses
the temple of Isis
The pronominal possessives hers, its, theirs, yours, and oneself have no apostrophe.
---
I think we can all agree that Linus is on par with Jesus and therefore a single apostrophe is correct.
Do you even lift?
These aren't the 'roids you're looking for.
The point of ZFS is it is *end-to-end*. Any part of the chain can silently introduce errors. Even if you believe "most likely an error will be in the memory buffer written by my application", I do not see how you can extrapolate that "checksumming file blocks is pointless."
Can you not imagine other failure modes? Even leaving aside unlikely (but possible) silent failures such as "wrote correct data to the wrong sector," what happens in an ordinary powerfail when only half of a mirror has been written? Ordinary RAID systems have absolutely no recourse. ZFS does.
Checksumming is of great protective value. You can verify this by following the ZFS mailing list. Silent write failures are more frequent than you might guess (for example, an often-reported cause is marginal power supplies).
you had me at #!
After a certain delay, you, as root, can remove it for good
That's the problem I have with userland based solutions. They require precognition-like ability so that you setup the scripts/cron jobs that will save your life in advance. Unfortunately, when you go around a large number of systems, or, as I mentionned above, use an application UI rather than the commandline for file manipulation, this kind of "I'll do some additional work against the very rare case where I really might need to undelete a file" doesn't really cut it (did I mention I was also lazy?) ...).
What I am saying is, a crude undelete is so simple to implement at the FS level, it should be a part of any modern filesystem, so that lazy bums like myself can get it at the flick of a switch when creating a new FS (mkfs --allow-undelete
But don't worry: I never blame anybody but myself when I inadvertently delete something (which hasn't happened that often, fortunately). I'm just annoyed that, as far as the end user is concerned, some of the native capabilities of filesystems seem to have regressed in the past 20 years. 20 years ago, I could easily undelete a file on my favorite O/S. Today I cannot...
Looks like these truths are not so self-evident after all...
well played! very nice.
Semi-automatic amateur armchair Australian philosopher; conjecture ready at any moment...
This is Slashdot, sir. Pedantry is what we serve.
The road to tyranny has always been paved with claims of necessity.
"Offcourse , we need to implement a sort of timeout"
Nah, it's all about lockless algorithms now, don't ya know. This one's simple; you get a cookie with the post form, and posts are displayed in cookie time order, not message post order. That way, person who hits 'reply' first gets first post as soon as they post it, pushing down any posts that've been made before first post is posted but after first post was initiated. Simple :-)
The revolution will not be televised... but it will have a page on Wikipedia
No, you pronounce 'es', yet nobody is advocating the use of es instead of 's everywhere just because it's pronounced that way...
It stands to reason that what stands to reason doesn't determine the rules of written english.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Perhaps because they are writing software which is by FAR most useful when it is used as far and wide as possible, while using a license which makes that goal extremely difficult to achieve, unnecessarily.
Honestly, the only reason anyone cares about Btrfs is because the license on ZFS is too restrictive for inclusion in Linux, and NOBODY has opted to write their own implementation under a GPL or other, freer, license.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Journaling does NOTHING to improve "data security". Absolutely nothing, either in practice, or in theory. What it does is obviate the need for fsck. It doesn't even do that particularly well, as non-journaled filesystems like FreeBSD's UFS2 can be used much more quickly after an unclean shutdown, and is extremely reliable.
No, disabling on-drive caching has to be #1. Without it, no file system can possibly act sanely.
Unless the RAM in question is battery-backed, as many higher-end RAID controllers are.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
I'm not running Ext4, I'm running Ext3, having switched over the last of the Ext2 FSs to Ext3. Now, I've got to deal with not only EXT4, but BTRFS? What kind of changes does it bring that I would/should give a !@# about?
Ext2 worked well. EXT3 was basically EXT2 but with journalling. What does BTRFS give me over EXT4, or for that matter, EXT3?
Sorry, just having trouble giving a damn....
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Why are developers who don't want their code to be ripped off (used without payment in a closed product) by companies and incorporated into a product are labeled zealots?
Perhaps because they are writing software which is by FAR most useful when it is used as far and wide as possible, while using a license which makes that goal extremely difficult to achieve, unnecessarily.
Um, "most useful" to *who*, exactly? Why is your, or anyone else's, convenience/preference more important than that of the software authors? By this logic, *all* software should be released into the public domain.
I know its an old-fashioned idea and all, but geez, whatever happened to letting software *authors* decide how their software may be used?
They would have gone the Microsoft route and created software that is completely proprietary
Instead, they just stole what they wanted from *BSD and created a system that is partially proprietary. That you think that is somehow better than "completely proprietary" is where the disagreement is. Three points still remain:
a) Apple took from the *BSD world, made a profit, and never returned in kind, and
b) Apple's OS is still proprietary: you can't write an "Apple OS application" using just the underlying BSD plumbing, and thus
c) The GP's points still stand, in particular: the *BSD's can't garner any momentum in the corporate space because most companies will never consider contributing back for fear of their competitors using their code against them. Since it isn't a level playing field, most commercial entities are only ever going to *take* from the *BSD world, not give back.
Little thing called the network stack that I'm sure we're all happy was BSD licensed?
Well, at least MS was happy they could snag that for free (then turn around and get others to pay *them* for it).
But, hey, if you think thats a great "arrangement", no problem, you're free to choose that path, just don't be too surprised that, having watched all this *taking* over the years, others have decided to go in a different direction...
No. I was alluding to GP's failure to make a good argument for supporting ZFS, using sound reasoning. I'm saying the truth of the premises doesn't imply the truth of the consequent.
ZFS on supported hardware is actually superior to ext4 on certain technical merits; primarily data integrity (checksumming), random write performance, and read performance (when massive amounts of RAM are available), and more advanced features (snapshots).
On the other hand, ext4 works on 32-bit processors (ZFS is only recommended to be used on 64-bit procs) with small amounts of RAM available, less than a GB; the minimum amount of RAM one should use ZFS with is 2gb, and 4gb or more is strongly recommended, above and beyond any RAM required by apps running on the machine.
ZFS can be used on low-memory, 32-bit machines. Or, at least, the ZFS support in FreeBSD works quite well on 32-bit machines with as little as 768 MB of RAM. There are a lot of FreeBSD users with laptops using ZFS, as well as a lot of test boxes setup with
Yes, ZFS works best on 64-bit systems with 4+ GB of RAM, but that's mainly due to the aggressive caching that ZFS does. The more RAM you have, the more caching it does, and the faster things are.
But that doesn't mean that it can't be tuned to work in RAM-constrained situations.
btrfs != reiserfs.
That is all.
I am not devoid of humor.
It's more than "works best on 64-bit", there are real issues utilizing ZFS for any production load on a 32-bit proc. It's probably not that bad on a laptop, as there's really no issue if your system crashes from time to time; Windows users are quite used to it.
The issue is ZFS caching causes free memory address space fragmentation on a 32-bit architecture, resulting it being unstable on 32-bit procs. Running out of allocatable virtual address space is basically equivalent to running out of memory; you may have plenty of RAM free, but your system can't service allocation requests larger than the biggest free fragment.
ZFS is as address space hungry as it is memory hungry.
For example, if you have a large filesystem shared out via NFS, at least in some versions you could cause a kernel panic on a 32-bit architecture by running a "find /" command.
Oh no! People are being CRITICIZED! Horror of horrors!
Look, software authors DO have the LEGAL right to decide what license to release their code under, which is, by far, the most important part. That doesn't change the fact that their choice in this case is foolish. And it certainly doesn't preclude them from criticism.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Oh no! People are being CRITICIZED!
...
That doesn't change the fact that their choice in this case is foolish
Responses of the form: "Duh, your stuuupid!" might technically be "criticism", but that doesn't go very far here, at least not for readers for which content actually matters.
Hint: You've yet to make any rational argument for why they're being "foolish", especially since you already admit:
software authors DO have the LEGAL right to decide what license to release their code under
This is especially weird here, as the software is an implementation of (AFAIK) an open specification, and can be reimplemented by anyone else if they want it under a different license. Can't stand GCC because of its license? No problem, use another C compiler.
So, don't like the license? Fine, then attack that, but just calling its users "foolish" only makes you sound like a troll. Or was that what you intended all along?
Its also a little amusing, given that the people you are calling "foolish" are actually employees of Oracle, IBM, Hitachi, and the usual Linux suspects, e.g. RedHat, SUSE, et. al. Best of all, the originators of BTRFS are the people that now significantly control ZFS's destiny, e.g. Oracle, and they were the ones who gave it the GPL license. Do you really want to continue calling the new masters of ZFS/Solaris/OpenSolaris "foolish"?
Maybe whats really got you irked is that the audience for BTRFS (the Linux ecosystem) will be more than large enough to ensure its long term success, whereas ZFS's future depends a lot on whether Oracle chooses to continue it into the long term. Its not clear yet what they're going to do with ZFS, but the Oracle dev who created BTRFS, Chris Mason (who BTW, was one of the ZFS devs too), and who is still leading its development (along with the others mentioned above) told its dev ml recently that everything was still a go with BTRFS as far as Oracle was concerned. So do you *still* want to continue calling Oracle "foolish"? :)
That being said writing a performance filesystem for Windows is much less easy than for Linux.
I have often wondered why there is not an XP replacement filesystem for consumers with better performance characteristics. XP degrades over time and one of the causes appears to be file access speeds degrading over time (it happens on XP systems without viruses or cruft).
Perhaps there is too much "noise" on the internet spamming optimising systems, so a working system can't get known? But perhaps a well known brandname could do it? Or is it due to non-file-system causes like registry-cruft and patch-cruft?
Happy moony
GPL licensed.
That's a bug, not a feature. Keep your politics out of my PC, and let me get on with what I want to do. I prefer "Free" software licences, "free as in freedom" (BSD, MIT, Mozilla, CDDL), not "free as in Follow My Rules" (GPL).
I wouldn't call that teasing that's been a time tested model for open source development contribute or pay. Trolltech used that for QT and everyone was OK with it.
Turning off caching is a terrible idea. What you want though is information being written in a way that is recoverable after an outage quickly and rectified slowly. A database based filesystem for example like you see on i-os.
Well, I was taught to drop the second s, and I'm not /that/ archaic.
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
Yeah just like you can modify a cookie from an online shop to make it look like you've paid for something to get them to post it out to you... oh or is it that the cookie is just a code used to lookup the actual values on the server?
And you'd also just put the cookie value in the form, so even with cookies blocked it would work.
You didn't think this one thru huh? :-p
The revolution will not be televised... but it will have a page on Wikipedia