How To Move Your Linux Systems To ext4 304
LinucksGirl writes "Ext4 is the latest in a long line of Linux file systems, and it's likely to be as important and popular as its predecessors. As a Linux system administrator, you should be aware of the advantages, disadvantages, and basic steps for migrating to ext4. This article explains when to adopt ext4, how to adapt traditional file system maintenance tool usage to ext4, and how to get the most out of the file system."
Re:Wait, what? (Score:1, Interesting)
Re:Not for the casual user (Score:3, Interesting)
But does it undelete... (Score:2, Interesting)
ext3 tops out at 16GB files? (Score:2, Interesting)
Re:To all ext3 users... (Score:3, Interesting)
XFS kills ext in terms of not losing data. I have recovered lots of data from failed drives that were XFS formatted. Not so with ext3 which tends to flake out and destroy itself when it gets bad data.
And don't even mention ReiserFS, that has always sucked. I have lost more data to Reiser than any other filesystem (ext is a close second though). Sometimes it would corrupt files just from rebooting the machine. I have never lost data on an XFS partition that wasn't due to hardware failure.
Re:Not for the casual user (Score:3, Interesting)
1 TB
500 GB
300 GB
When they decide to fsck at the same time, it can take 1/2 hour or longer to get to the login screen.
Re:Not for the casual user (Score:3, Interesting)
I transcode my Myth stuff on an ext3 partition, and occasionally get complaints about the large data size without having the right options set. But it works.
Re:Not for the casual user (Score:5, Interesting)
Re:Preempting the prefix war (Score:3, Interesting)
In any spoken language, different sounds are loosely associated with different ideas. As a simple example, voiceless sounds, like p, k, t, f, and s, are well suited for pointed use, as in pejoratives; and r, especially the alveolar trill variety, is associated with intimidation or primality. These associations are made either because it sounds like something else ("rrrr" sounds like an animal's growl or roar -- notice the Rs in "growl" and "roar"?) or because the sound serves a purpose (hard, clipped sounds serve well as punctuation -- notice all the hard sounds in "punctuate"?). In the latter case, combinations of sounds can invoke a wide array of ideas or feelings. Utilization of these things is key to a good punchline or to controlling semiconscious undertones of speech. I admire Dr. Seuss in particular for his mastery of sound combinations in making up suitable words to balance sing-song silliness with gravity and purpose.
Now, returning to "tebibyte" and all the other -bibytes, soft, voiced consonants like B are associated with childishness (a baby might make these sounds), silliness, bounciness, or informality. Two Bs in a row are especially so: bib, baboon, babble, bob, boob. The reason tebibyte sounds "stupid" is that it describes a technical idea using unsuitable sounds.
This being said, if you were used to using the word, you wouldn't think twice about it. You would probably complain about "flop" and "watt" in the same way if the words were new, but established use overrides the weak sound associations. The President could be instead called the Biggyloppalo and few would care, as long as the term were already established in the common vocabulary. I'd think people would move on even if a video game console were named something as ridiculous as "Wii"
As for my opinion on the matter, I'm in favor of it. The SI prefixes are already assumed to be powers of 10 in all other fields except the computer and information sciences. Tebibyte will maybe sound silly for awhile, but the problem will go away given time. And I, for one, look forward to buying futuristic data storage without feeling a little cheated.
Re:undelete (Score:2, Interesting)
Re:Not for the casual user (Score:5, Interesting)
That said, ext4 is unstable. It can easily eat your data. Just say NO to moving your filesystem to ext4 - for now.
Re:To all ext3 users... (Score:5, Interesting)
ext3 is both so slow and so bottlenecked that mythtv had to implement a special "slow delete" mode which gradually truncates files instead of just unlinking them. Without the "slow deletes" mode, you get hiccups in any shows that are being recorded while old shows are deleted.
On my system, deleting a 20GB file can take a minute on ext3 (and the filesystem is completely locked - all other processes are blocked), but on ntfs it is almost instantaneous.
Re:Not for the casual user (Score:3, Interesting)
Re:But does it undelete... (Score:2, Interesting)
Hear, hear. I second this.
You know why I want this so much? Because I used to have this. When I ran Windows 98 with Norton Utilities I had a feature called the "Norton Protected Recycle Bin". It had the following properties:
0) When a file was deleted by any means it would go into the NPRB. If you copied file "foo" onto file "bar", the old "bar" would go into the NPRB. If you went into a DOS shell and ran the "del" command, the files you deleted would go into NPRB.
1) The original name, original location, timestamp of the file at the time of deletion, and time of deletion were all saved and were visible in the list of deleted files.
2) You could specify a do-not-save list, both by filespec (example: do not save "*.tmp", "*.bak", etc.) and by location (example: do not save any files in C:\Windows\Temp, etc.) And sensible defaults were provided (all my examples here were set by default, plus more).
3) Your deleted files would age out. It would automatically purge files that were deleted more than 14 days ago (by default; of course you could change it). I liked to keep mine set for 3 days auto-purge; I pretty much always un-deleted something seconds after deleting it, so the longer period didn't help much. And disks were small in those days...
I don't think it would ever empty the NPRB automatically just because you were out of disk space. But it was trivial to right-click on the Recycle Bin icon on the desktop and choose "Empty Norton Protected Recycle Bin".
To do the above properly in Linux, the file system should have a way to specify whether a given file should be saved or simply deleted. The Ext2 file system has an attribute you can set on a file requesting that it be saved instead of deleted; read the man page for chattr(1) and look for the 'u' attribute. (Then read the "Bugs" section at the end, where it says that the undelete feature has never actually been implemented.)
The file system should handle the deletion or saving of files, and then user-space utilities should be able to get a list of saved files, undelete a saved file, empty the saved files, etc. Of course users should only be able to delete their own files, so ownership and permissions need to be checked too.
With this feature, and today's huge hard disks, a Linux desktop would be great for ordinary users.
P.S. If you have Vista, and you get Norton Utilities, is there still a Protected Recycle Bin feature? Or is that one of the things that Vista loses? For that matter, can you still do this in XP?
steveha
Re:Not for the casual user (Score:3, Interesting)
As for your other points, it's largely a packrat mentality. There have been times when I wished that I could rent a movie, only to find that it's no longer available on DVD. Sometimes Netflix has it, sometimes they don't, but when production stops, it stops, and as copies of the movie wear out, it becomes much harder to come by. That makes purchasing them and backing them up on magnetic media more attractive, even if I may not get around to watching the films again any time soon.
Re:Not for the casual user (Score:3, Interesting)
It is just more productive to grab the DVD.
Re:Not for the casual user (Score:3, Interesting)