by ghmitch » Sep 23rd, '11, 06:06
When the time comes, BtrFS is destined to replace ext4 as the Linux FS of choice according to the top Linux file system devs. In fact, ext4 was created as a bridge of sorts between the old ext3 and BtrFS. The primary hang up with BtrFS at this point is lack of a comprehensive fsck tool. That is supposedly being addressed now. Other problems with BtrFS include issues with legacy grub which is not being updated to support the complexity of BtrFS. Moving to grub2 with label support AND GPT support would be helpful, but moving to grub2 gets us into the old chicken/egg conundrum. If we move to grub2, we risk incompatibility with other distros on dual boot systems. Additionally complicating this whole process is the need for a workaround for older non-EFI boards, since grub boot loader is unable to install on ordinary GPT hard disks without the addition of a dedicated bootloader partition. So there are a whole lot of issues to be unraveled before we can move forward to the future. The problem is that many of us really *need* this new technology *now*. But the huge risk is instability if we move forward too fast. I am using Mageia right now INSTEAD of Mandriva for this very reason. Mageia is being very conservative on issue like this whereas Mandriva has always tended to push the envelope. I really *like* the advanced "features" of Mandriva, but I simply can't deal with the side effects. So I am very happy that Mageia is *wisely* waiting until some of these gotcha's get worked out before trying to push forward.
While there is a lot to like about XFS, it is a non-starter for me simply because it is not portable across system architectures. Unlike all other file systems you can not read an XFS file system from a 32 bit machine on a 64 bit machine or visa verse. They are incompatible. That doesn't work for me. Additionally, XFS is not native to Linux and there are some questions about its future maintenance and development. BtrFS, on the other hand, will continue to be supported and developed long into the future. While ext4 is based on ext3, BtrFS is based on ReiserFS. So a lot of the concepts behind BtrFS are not new but are proven concepts from the proven Reiser system. I *REALLY* do want to move on to BtrFS, but I am not willing to pay the price of getting on board before it is *ready*.