An In-Depth Look at Reiserfs - page 6
Included in the Linux kernel
Reiserfs isn't perfect, and has problems and limitations like any other software. Because it changes the conceptual way in which the disk is allocated and managed, Reiserfs doesn't work well with network file system (NFS) servers. There are some patches available to remedy part of the problem, but they don't completely solve it. Likewise, using software RAID to create fault-tolerant drive arrays doesn't work under Reiserfs (but hardware RAID is fine). As with any other piece of software, you have to look at Reiserfs in relation to your needs and the system's intended purpose, and then make a reasoned decision as to whether it's the right tool to use.
Performance gains under Reiserfs can be substantial, or can
be miniscule, depending on what you are doing. I have found
that Reiserfs is extremely responsive for most of my work,
and I wouldn't want to live without it. Compiling source code,
something that typically opens hundreds or thousands of files
in rapid succession, really zooms. The biggest difference I
have noticed is when using the
find command to scan large
directory trees. Scans that used to take thirty seconds or
more now take just five or ten seonds. Copying large files
takes just about the same amount of time as with ext2, though
deleting unwanted files is significantly faster.
Traditional filesystems such as ext2 can be well-designed and reliable, and I certainly have found ext2 to be quite acceptable in the past. I have never, ever, lost a filesystem after a crash under ext2. Yet the long bootup delay while ext2 does its checking is annoying, especially on a test machine where crashes are more frequent because, well, it's a test machine. All things considered, I am thoroughly sold on journaled filesystems in general and Reiserfs is certainly a fine implementation.