5.13. A Comparison of Filesystem Types

Unlike other operating systems, Linux supports several different types of filesystems that fully support UNIX file permissions and ownership information. Originally, ext2 was the only choice, but newer kernel versions and distributions have added support for ext3, reiserfs, and xfs. This list explains the benefits of each of these alternative filesystem types.

New Linux Native Filesystem (ext3) Very similar to ext2, but with support for journaling. This means that if your system crashes or loses power without having a chance to properly unmount its filesystems, there is no need for the lengthy fsck check of the entire ext3 filesystem that would be needed with ext2.

Because ext3 filesystems are so similar to ext2, they are stored on disk in almost exactly the same format. This means that it is relatively simple to convert an existing filesystem to ext3 by creating a special journal file.

Rieser Filesystem (reiserfs) ReiserFS is a totally new filesystem designed to be faster and more efficient than ext2. It supports journaling like ext3 does, and deals much better with large numbers of small files than other filesystems. It is probably not as mature as ext3 or xfs, however, and does not support quotas.

SGI Filesystem (xfs) XFS was originally developed by SGI for its IRIX operating system, and if you are running Webmin on IRIX you can mount xfs filesystems as well. It supports journaling and includes native support for ACLs (access control lists) and file attribute lists. The ACL support in particular is very useful, because it allows you to grant access to files in ways that would be impossible with the normal UNIX user/group permissions. XFS has been used for several years on IRIX, so it should be reasonably mature and reliable.

IBM Journaling Filesystem (jfs) JFS was originally developed by IBM for use on its AIX and OS/2 operating systems, but has recently been ported to Linux. It supports journaling and large (64-bit) file sizes, but does not current support quotas or ACLs. Because JFS has been used for years on IBM operating systems, it should be reasonably mature. It is quite new on Linux, however, and so may not be as well tested.

To see which of these filesystem types are supported by your system, go into the Partitions on Local Disks module (covered in Chapter 8) and select an unused partition of type Linux. At the bottom of the page will be a form that you can use to create a new filesystem on the partition in one of the types that is available on your system. Most new Linux distributions will support ext3, some will support reiserfs, but only a few include xfs support.

Linux also supports several older filesystem types such as ext, xiafs, and minix. You will never need to use these unless you have an old disk formatted with one of them.