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EXT4 Is Coming
ah admin writes "A series of patches has been proposed in Linux kernel mailing list earlier by a team of engineers from Red Hat, ClusterFS, IBM and Bull to extend the Ext3 filesystem to add support for very large filesystems. After a long-winded discussion, the developers came forward with a plan to roll these changes into a new version — Ext4."
Let me put it this way, it's a little past the average slashdot porn collection:
ext3: 8TB total, 4TB files
ext4: 32 zettabyte (1024*1024*1024 TB), 1 exabyte files (1024*1024 TB)
Beyond that, it doesn't seem to actually change much.
Live today, because you never know what tomorrow brings
Ummm...zfs exists, ext4 doesn't. Yet.
Lump lingered last in line for brains, and the ones she got were sorta rotten and insane.
It's dishonest to put something in quotes when it's not a direct quote. The exact quote is:
There's a substantial difference between saying that something is more stable "as a result" of something and more stable "because" of something. He's not claiming that being out longer intrinsically makes it more stable as your misquote suggests, he's claiming that it led to reiserfs becoming more stable - because of the practices he mentioned.
In short - something being out longer == more stable? No. Something being exposed to lots of real-world use and receiving only bugfixes == more stable? Yes.
He didn't quote Adam Smith, he drew an analogy between what he was saying and the network effect. It's an entirely reasonable analogy.
What ridicule? He's actually supporting that approach. For example:
Would you care to point out where you thought he was ridiculing the UNIX approach?
Yeah, they look dumb, don't they?
I can only assume you mean something other than "technical".
Dancing trees are a fundamental part of the design. How are you meant to understand the filesystem without understanding dancing trees?
Ah, you don't mean technical at all, you mean practical for somebody who is entirely uninterested in the way the filesystem works. Perhaps Reiser4 Transaction Design Document is what you are after, but I doubt it.
Bogtha Bogtha Bogtha
ext3: 8TB total, 4TB files
u lts).
ext4: 32 zettabyte (1024*1024*1024 TB), 1 exabyte files (1024*1024 TB)
Are they just going to work on improving the 8TB paper limitation, or are they actually trying to improve on ext3 scalability? Which, currently tends to suck the big one, especially on a significant number of disks (eg: http://scalability.gelato.org/DiskScalability/Res
I also seem to keep coming up against a pretty hard 2TB block device limit in Linux (eg LVM2 lv size, LUN size for fibre attached SAN, etc). I don't really know what the reasons for it are, anyone know what technologies allow for larger single partitions?
Anyway, I've long ago settled on reiserfs (3) for speedy random access to small files, and XFS for file server type applications; though I still wonder why RedHat doesn't include any "enterprise" filesystems by default in their "enterprise" products (I know, I know, you can enable it - I did say "by default").
sic transit gloria mundi
I'm as big a Linux fan as anyone, but one glaring thing that it needs is some better filesystem tools. Don't get me wrong -- they've come a long way in the last couple years -- but compared to something like AIX it still has a little ways to go. Here's one feature that causes a challenge: Linux filesystems and the underlying logical volume layer is largely decoupled. You have an immense amount of flexibility but as a consequence, the filesystem and volume layers don't always communicate as well. For example, the AIX JFS2 tools allow you to dynamically grow/shrink filesystems. This functionality exists in Linux for some filesystems (EXT3, ReiserFS) but the procedure varies depending on how the filesystem is constructed. And at this point, I'm not fully convinced of its stability as I've recently (three months ago) lost an entire disk after a dynamic resize on an LVM backed EXT3 partition. I have yet to reproduce the failure but it occurred with a 95% full /home and a kernel compile going full tilt.
But I'm amazed at how quickly these features are being integrated. There's functionality in Linux that allows me to easily create file-backed volumes, remote volumes, SAN LUNs, etc.. The "resize in a single command" is not fully there yet, but within 6 months I'd expect it to be.
"I consider it to be about as stable as XFS."
/video and /home partitions on XFS for... WAY too long, several years, same drives.
I have had my
(I just keep adding on)
I lose power a lot where I live (glitches) and XFS has been utterly bullet proof.
(This filesystem has bee thru 3 motherboards, several linux distros (1 mb dead/2 upgrades), 2 cases, and so on)
If Reiser4 is about as stable as XFS, I'll glady switch everything over tomorrow on my MythTV box.