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Why Redhat Choose ext3 For 7.2
mz001b writes "There is an interesting article from RH posted on LinuxToday discussing why they chose ext3 over the other available journaling filesystems (ReiserFS, xfs, jfs,...) for RH 7.2"
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Linux still is about choice. You can choose Red Hat, or Debian, or Suse, or Mandrake, or Progeny, or whatever you want. Inside those choices, you can choose to install whatever packages you like. And you can choose whatever filesystem suits your fancy. Red Hat isn't telling you what works for you, and it isn't telling you that you shouldn't use a certain filesystem. It says that very plainly in the article. Please read them before posting drivel like this.
Every once in a while I like to masturbate a new word into my vocabulary, even if I don't know what it means.
I've done some research on the different filesystems. The machines I used were all old Dell Dimension XPS D233's, 64M memory, 2G HDD's.
Machine 1: Redhat 7.0/ext2
Machine 2: Debian Woody/ext3
Machine 3: Slack 7.0/reiserfs
Test 1:
The machines were elevated to a distance of 5 stories to the rooftop of a local building, or approximately 70 feet off the ground. Each machine was dropped veritcally then tested to see if this damaged the filesystem.
Machine 1: Destroyed
Machine 2: Destroyed
Machine 3: Almost Destroyed, but made funny noises and started to smoke during CMOS check
Test 2:
Unable to test due to unpredicted destruction in test 1.
Conclusion:
No current filesystem for mainstream Linux systems is capable of surviving a 5-story vertical drop. Until this feature is implemented in an open source file system, it will be hard for that FS to be widely accepted.
why did they choose to use ext3 ?
ofcourse its the migration path. Users can choose to install ext3 and later if they want to they can choose to go back to ext2. forward and backwards compatiblity makes ext3 a much more friendly jouraling filesystem for businesses. Some of the intranet servers cannot risk to backup and hope the new filesystem to go up working alright. Ofcourse there are better journaling filesystems out there. But the choice to use ext3 is good one since, its mature,stable and easier to administrate and use. Easier to administrate and use the keywords here. Any kernel out there can read an ext3 partition without extra modules. So it definitely plays well with others. Is there any other journaling filesystem that can say this ?
The article at LinuxToday isn't about RedHat prefering ext3 over other journaling filesystems. It's merely an explaination of why they decided to include ext3 in the new RedHat 7.2.
The only comparison made is between ext3 and ext2 where they explain the advantages of a journaling system.
Linux has never crashed on me without a hardware problem causing it (not an exaggeration), but that doesn't mean we haven't had plenty of hardware problems, and each time there was a failure, the fsck would take 30-45 minutes. My first thought was ext3, but... heh. It was always grayed out in the kernel config menus. Not a good sign. ReiserFS on the other hand was immediately available.
Of course, you don't trust your data to something without being damn thorough about it, so I did a bunch of tests on staging servers (which went great) and I spent a lot of time reading Hans Reiser, who impressed me considerably as a smart person with a lot of good ideas. We made the move this spring and have had zero problems with the filesystem during normal operations. Zero. It's blazing fast on our tests, it appears to scale beautifully, and if I go down, I have no wait time anymore coming back up.
Of course, I keep up with the kernel changes and upgrade when I see updates relevant to the filesystem.
It's not a perfect package, but nearly. Its consistency checker/repair tool (reiserfsck) is not finished (as its messages vigorously warn). Now, remember, this is not the same thing as e2fsck. You are not using it in the same role, its purpose is much more specialized (disaster recovery), so the significance is different. Still; we came to use it during several of the many times high-speed SCSI chomped on our asses and corrupted data. We have backups, of course, but I wanted to see what the tool was capable of. In several cases it was able to successfully rebuild the filesystem, very slowly, with --rebuilddb, but in several other cases, the tool would dump core, which, if you were one of those fools without a backup, would leave you stranded.
Even in this, however, I was reassured; the maintainer of the tool answers emails quickly and was eager to try to troubleshoot the problem. I thus have no doubt that it will quickly mature into something quite good. It's just not there at this moment.
On the whole I would say I'm extremely happy with ReiserFS; we've punished it here pretty brutally and it's passed every test. I don't have any experience with ext3, but anecdotally I'm told it's less mature. Still, I have nothing against it. I can only comment that I hope Redhat's upgrade process from 7.1 to 7.2 will at least take reiserfs into account, instead of breaking the way it did from 7.0 to 7.1.
We're on the road to Tycho.
I'm suprised that more people haven't said anything about XFS. I've been using for awhile now at home and on a production fileserver at work for awhile now and haven't experienced any problems. The only thing at all that has been a worry is the fact that Grub can not yet read XFS, so you have to create a small boot drive at the beginning. At least with XFS, the filesystem has already been designed and tested for years by SGI, and the only matter was porting it to Linux. From what I've seen with ReiserFS, they are still trying to decide on features and on how it is going to go about doing things. That's fine and all, but I don't want to end up having to backup and restore my filesystem a few times as they decide to impliment a new "everything and the kitchen sink" feature. If I'm doing something for file integrity and security, I'd rather have something that I know has been working for years now in a high performance environment. Just so this won't be considered offtopic, I would say that I can see why ext3 would be preferred by Redhat over Reiser (with the in-house development, and the easier migration), and hey, it will probably be "good enough" for most people (and certainly some kind of journaling is better than plain ext2), so hey, good for Redhat, and good for their users. I'll continue using XFS, but that's what's nice about choice anyway, right?