| Developer(s) | Stephen Tweedie |
|---|---|
| Full name | Third extended file system |
| Introduced | November 2001 with Linux 2.4.15 |
| Preceded by | ext2 |
| Succeeded by | ext4 |
| Partition IDs | 0x83 (MBR) EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 (GPT) |
| Structures | |
| Directory contents | Table, hashed B-tree with dir_index enabled |
| File allocation | bitmap (free space), table (metadata) |
| Bad blocks | Table |
| Limits | |
| Max volume size | 4 TiB – 32 TiB |
| Max file size | 16 GiB – 2 TiB |
| Max no. of files | Variable, allocated at creation time[1] |
| Max filename length | 255 bytes |
| Allowed filename characters | All bytes except NUL ('\0') and '/' |
| Features | |
| Dates recorded | modification (mtime), attribute modification (ctime), access (atime) |
| Date range | December 14, 1901 – January 18, 2038 |
| Date resolution | 1 s |
| Attributes | allow-undelete, append-only, h-tree (directory), immutable, journal, no-atime, no-dump, secure-delete, synchronous-write, top (directory) |
| File system permissions | Unix permissions, POSIX ACLs and arbitrary security attributes (Linux 2.6 and later) |
| Transparent compression | No |
| Transparent encryption | No (provided at the block device level) |
| Data deduplication | No |
| Other | |
| Supported operating systems | Linux, BSD, ReactOS,[2] Windows (through an IFS) |
ext3, or third extended filesystem, is a journaled file system that is commonly used with the Linux kernel. It used to be the default file system for many popular Linux distributions but generally has been supplanted by its successor version ext4.[3] The main advantage of ext3 over its predecessor, ext2, is journaling, which improves reliability and eliminates the need to check the file system after an improper, a.k.a. unclean, shutdown.