From Fedora Project Wiki
File Systems
Ext4 - The default file system
- Serious notes needed about upgrading and downgrading. Following content uses this reference: http://kernelnewbies.org/Ext4
- Improvements in file systems and sizes
- File system size increased to one exabyte (1 EiB)
- File size limit is sixteen terabytes (16 TiB)
- No limit on number of sub-directories
- Performance
- Extents increase performance in certain situations, especially large files
- Multiblock allocation is a new file block allocation method with faster write speed
- These combine with delayed allocation of blocks for better performance and fragmentation