General purpose journaling filesystem supported by Linux since 2.4.1.
ReiserFS is a general-purpose, journaling filesystem supported by Linux since 2.4.1. It was written by a group at Namesys, headed by Hans Reiser.
ReiserFS has some important features:
- Filesystem journaling - as opposed to to the then current ext2
- Online Filesystem Growth
- Tail Packing - reduces filesystem fragmentation
- Optimized for small files
However, it also has some drawbacks:
- Use of the Big Kernel Lock (BKL) - limits filesystem operations to a single core
- Lack of a true defragmenter
fsckcan corrupt an already corrupted filesystem- Lack of migration path - Reiser4 is not planned to be backward-compatable