Life and times of the classic ext Linux filesystem
The Filer
The ext filesystem celebrates its 25th birthday next year. A brief tour of ext history will give you some insights into how this classic Linux filesystem works – and how it has evolved to meet users' needs.
When Linus Torvalds developed the first early versions of Linux in 1991, he used the Minix filesystem by Andrew S. Tanenbaum. The Minix filesystem was part of the legacy of the Minix Unix clone [1], which Tanenbaum created for teaching purposes. Some restrictions, such as a maximum file name length of 14 characters or the file size limit of 64MB, gave rise to the need for a filesystem specially developed for Linux: The birth of the Extended Filesystem, or ext, followed shortly afterward.
French software developer Rémy Card released the first version of ext in 1992, making it possible to save files of up to 2GB on Linux. The permissible length for file names grew to 255 characters. Although ext got many things right in the first version, it was hardly up to professional requirements. For some applications, ext suffered from severe fragmentation, and it was impossible to store different timestamps for access and modifications of the inode and file.
Successor Ext2
When designing ext2, the developers adopted many best practices and principles of the then-widespread Unix Berkeley Fast File System [2]: Accordingly, an ext2 filesystem divides the storage medium into blocks from a logical perspective, then strings the blocks together. The default block size is 4KB.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Digital Autonomy
• The Answer Was Already on the Shelf
• Changing the Chip Industry: How Public Investment Has Grown Open Silicon
• United Nations Open Source Portal Goes Live
• EU Open Source Strategy Plays Key Role in Tech Sovereignty Package
• France Says “Au Revoir” to Microsoft
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Pine64 Halts Production of Linux Devices
With continued DRAM and eMMC shortages, Pine64 has decided to discontinue production of Linux devices.
-
The Bullet-Proof KDE Software Initiative Is Coming
KDE, Techpaladin, and Kubuntu Focus have announced a new initiative that will provide at least three years of support for KDE Plasma 6.6 LTS and related software.
-
Linux Mint Shares a Possible Kernel Cleanup Solution
For those on Linux Mint who like to keep multiple kernels around but don't want them to take up too much space, you might be getting a new automated tool.
-
CachyOS Gets an Update
CachyOS August 2026 release is now available with the latest version of KDE, some new features, and plenty of improvements.
-
The Linux Kernel Dev Staging Area Now Rejects AI-Generated Patches
Unless a kernel patch is a valid security fix, it will be rejected if it was created using AI.
-
Linux Surpasses Double-Digit Market Share
According to two sources, the Linux operating system has hit a major milestone in market share that naysayers thought would never happen.
-
AI Helped Develop a Linux Exploit
A use-after-free race exploit was discovered and exploited on CentOS Stream 9.
-
Yet Another Linux Kernel Vulnerability Discovered
Affecting millions of systems, a kernel flaw discovered by Qualys could allow users to gain root privileges.
-
Ubuntu 26.10 to Include Ubuntu Certified Hardware Check
If you've ever wondered if your laptop or PC is officially certified to run Ubuntu, that curiosity will soon be met.
-
Substantial Update to IPFire Now Available
The lastest version of IPFire features a fundamental change to how the system handles DNS.