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
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
-
2,000 Vulnerabilities per Linux Release
Thanks to AI bug hunters, the Linux kernel is seeing record numbers of vulnerabilities, and it's overwhelming developers.
-
Linux Exempt from California’s Age Verification Law
So long as Linux is distributed under the GPL, MIT, BSD, and Apache licenses, the OS is exempt from being required to verify the age of its users in California.
-
Roll Out the Cake: Linux Turns 35
35 years ago, a Finnish student began a humble project that would forever change the course of technology.
-
China Switching from Windows to Linux
China has ordered several government agencies to drop a Chinese-developed version of Windows 10 in favor of either KylinOS or UOS.
-
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.
