Mastering Linux Kernel Development

Ext4

Implemented as a replacement to Ext3 with enhanced features, Ext4 first appeared in kernel 2.6.28 (2008). It is fully backward compatible with Ext2 and Ext3, and a volume of either type can be mounted as Ext4. This is the default ext filesystem on most current Linux distributions. It extends journaling capabilities of Ext3 with journal checksums which increases its reliability. It also adds checksums for filesystem metadata and supports transparent encryption, resulting in enhanced filesystem integrity and security. Other features include support for extents, which help reduce fragmentation, persistent preallocation of disk blocks, which enables allocation of contiguous blocks for media files, and support for disk volumes with storage ...