After 11 months of development, OpenZFS 2.4.0 has been released. This project focuses on developing the ZFS file system implementation for Linux and FreeBSD, previously known as “ZFS on Linux”. The project, initially limited to creating a module for the Linux kernel, merged with code from FreeBSD and was recognized as the main implementation of OpenZFS.
OpenZFS has been tested with Linux kernels from 4.18 to 6.18 and all FreeBSD branches starting from 13.3. The code is distributed under the free CDDL license. It is already integrated into FreeBSD and various Linux distributions including Debian, Ubuntu, Gentoo, NixOS, and ALT Linux. Packages for major Linux distributions, such as Debian, Ubuntu, Fedora, RHEL/CentOS, with the new version are in preparation.
OpenZFS provides ZFS components for the file system’s operations and volume manager’s functions. Components include SPA (Storage Pool Allocator), DMU (Data Management Unit), ZVOL (ZFS Emulated Volume), and ZPL (ZFS POSIX Layer). The project also supports using ZFS as a backend for the Luster clustered file system, based on the original ZFS code from the OpenSolaris project enhanced by the Illumos community.
The project is developed with the involvement of Livermore National Laboratory’s employees under a contract with the US Department of Energy. The code is distributed under the CDDL license, which, although incompatible with GPLv2, allows for autonomous loading as a separately supplied module, avoiding integration issues with the Linux kernel.
Main changes in the new version:
- Implemented ability to set default quotas for users, groups, and projects instead of individual IDs.
- Added the option to rollback the direct I/O mode (O_DIRECT) to utilize uncached I/O for non-aligned requests.
- Introduced a unified algorithm for limiting write rate and block allocations, reducing vdev fragmentation.