File Systems In Linux; Terminology - Novell LINUX ENTERPRISE DESKTOP 10 SP2 - DEPLOYMENT GUIDE 08-05-2008 Deployment Manual

File Systems in Linux

SUSE Linux Enterprise® ships with a number of different file systems, including Rei-
serFS, Ext2, Ext3, and XFS, from which to choose at installation time. Each file system
has its own advantages and disadvantages that can make it more suited to a scenario.
Professional high-performance setups may require a different choice of file system than
a home user's setup.

22.1 Terminology

metadata
A file system–internal data structure that assures all the data on disk is properly
organized and accessible. Essentially, it is "data about the data." Almost every file
system has its own structure of metadata, which is part of why the file systems
show different performance characteristics. It is extremely important to maintain
metadata intact, because otherwise all data on the file system could become inac-
cessible.
inode
Inodes contain various information about a file, including size, number of links,
pointers to the disk blocks where the file contents are actually stored, and date and
time of creation, modification, and access.
journal
In the context of a file system, a journal is an on-disk structure containing a kind
of log in which the file system stores what it is about to change in the file system's
metadata. Journaling greatly reduces the recovery time of a Linux system because
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