From Fedora Project Wiki

The current upstream wiki for the EXT4 effort is at This page is only retained as a historical reference

EXT3 Filesystem Extents/64bit Project

Recently, many disk vendors are manufacturing disk drives using the perpendicular recording technology, which allows the density of a disk platter to go up to 30 gigabits per square inch, and that translates to 1 terabyte on a 3.5-inch hard drive.

The increase in the disk drive's capacity highlights the need for larger filesystem support. The current limits for ext2/ext3 filesystem are 2 terabytes with 1KB blocks, and 8 terabytes with 4KB blocks. In order to accommodate the growth of disk size in the next 2-5 years, the ext3 filesystem capacity needs to expand, hence the extents/64bit project.

Current Status

Ext4 filesystem has merged into 2.6.19 as a development version. The current features and future plans are documented in;a=blob;f=Documentation/filesystems/ext4.txt

Ext3 Filesystem Extents

The ext3 extents (a.k.a. 64bit) patchset that has been proposed and submitted upstream for comments. The patchset was originally developed by the developers at Bull; however, there are many other aspects of the ext3 64bit support that weren't addressed by the original patchset. This wiki page is to explain and track the progress of this project:

Bull's opensource website is located at:

Bull's opensource webpage explains a lot of the changes in the original patchset. Most notably, the EXT3 extents with 64bit physical block patch and 64bit logical block patch.


Current Patchset



Conference Call Minutes

May 3, 2006 ext3-devel/ext3minutes-20060503

May 10, 2006 ext3-devel/ext3minutes-20060510

May 17, 2006 ext3-devel/ext3minutes-20060517

May 31, 2006 ext3-devel/ext3minutes-20060531

June 21, 2006 ext3-devel/ext3minutes-20060621

June 28, 2006 ext3-devel/ext3minutes-20060628


ext2-devel mailing list:

ext2-devel mailing list archives

ext2 project home

e2fsprogs project home

State of the Art: Where we are with the Ext3 filesystem

Bull's Ext2/Ext3 improvement project

Wikipedia Ext3 page