Filesystems: ext4, btrfs, zfs ... hammer?

There are several new filesystems coming out of the wild. A whole new herd of beasts trying to be on top of the food chain. I'll take a brief look at them and try to uncover a stealthy one.

I'll start with, maybe the most interesting new filesystem, when it comes to features, which is ZFS. It has great volume management capacities included, snapshots!, easy to use management utilities and is very comfortable when it comes to share information (SMB, iSCSI, NFS, etc ...). It is also enjoying a good momentum since it was maybe the first one to include a whole set of features in "just" the filesystem. Con sider it a really good filesystem to create NAS/SAN devices.

To catch up, the linux comunity has develoved a nice ext4 filesystem that can kkep the pace of ext3 while adding some new features. There is a great descriptive article in linux magazine about it. Ext4 is considered to be [almost] production ready. For new features Btrfs is the development branch that will take the torch of filesystem lead (in the linux world, of course). This one includes "da'feature" which is snapshots. On the shoulder of this giant stand two interesting projects which are CRFS and POHMELFS, out of which LWN made a really nice article, but this are yet to come.

And, the last (but, of course, not least) of the new beasts in the town, HAMMER. The filesystem son of Matt Dillon, which comes with the OS son, Dragonfly BSD. It's a ... high availability, redundant, 64bit filesystem which was included in the 2.0 release of DragonflyBSD. HAMMER does with machines (in some way) what zfs did with partitions. To get an idea on what it will be able to do, take a look at Matt's presentation during NYCBSDCON08. Expect its features in Linux through its port or in the Tux filesystem.