Introduction (see https://discourse.ubuntu.com/t/plucky-puffin-release-notes/48687 for more info) Introduction These release notes for Ubuntu 25.04 (Plucky Puffin) provide an overview of the release and document the known issues with Ubuntu and its flavours. Support lifespan Ubuntu 25.04 will be supported for 9 months until January 2026. If you need long term support, we recommend you use Ubuntu 24.04.2 LTS 539 which is supported until at least 2029. Upgrades Upgrades to to Ubuntu 25.04 will refresh seeded snaps to the appropriate snap channels, regardless of what was being tracked before. Snaps that are newly-seeded will be installed during the upgrade. In particular, the following snaps will be installed or refreshed on upgrade: Early upgrades may wish to perform these updates manually. New features in 25.04 Updated Packages Linux kernel 6.14🐧 This release delivers the latest Linux kernel, following Canonical’s new policy. Kernel developers can now make use of a new scheduling system 63, “sched_ext”, which provides a mechanism to implement scheduling policies as eBPF programs. This enables developers to defer scheduling decisions to standard user-space programs and implement fully functional hot-swappable Linux schedulers, using any language, tool, library, or resource accessible in user-space. A new NTSYNC driver that emulates WinNT sync primitives is also available, delivering better performance potential for Windows games running on Wine and Proton (Steam Play). The “bpftools” and linux-perf tools have been decoupled from the kernel version, making dependency management easier for developers working with containers. These tools are now shipped in their own packages. Other features can be found in the Linux 6.14 upstream 159 changelog. After the generic kernel grew the ability to tune responsiveness at boot time 67, the linux-lowlatency binary package has been retired in favour of a combination of linux-generic and a new userspace lowlatency-kernel package, responsible of tuning the grub cmdline. systemd v257.4 The init system was updated to systemd v257.4. See the upstream changelog 55 for more information about individual features. To highlight a few things: In Ubuntu, systemd is no longer built with utmp support. Among other things, this means that systemd’s default /usr/lib/tmpfiles.d/systemd.conf no longer creates /run/utmp. There is currently this known bug (LP: #2103489 18) in Ubuntu 25.04, that prevents ‘who’ from properly working and requires a coreutils rebuild. The complete removal of support for cgroup v1 (‘legacy’ and ‘hybrid’ hierarchies) is scheduled for v258. Support for System V service scripts is deprecated and will be removed in v258. Please make sure to update your software now to include a native systemd unit file instead of a legacy System V script to retain compatibility with future systemd releases. Netplan v1.1.2 :globe_with_meridians: Adding support for wpa-psk-sha256 WiFis and allowing to configure routing-policy on the NetworkManager backend (LP: #2086544 11). Additionally, the version shipped in Ubuntu enables new functionality 27 in systemd-networkd-wait-online to wait for DNS servers to be configured and reachable, before considering an interface to be online 22. Toolchain Upgrades :hammer_and_wrench: GCC :cow: a snapshot of the upcoming GCC 15, binutils updated to 2.44, and glibc to 2.41. Python :snake: is updated to 3.13.3 LLVM :dragon: now defaults to version 20 Rust :crab: toolchain defaults to version 1.84 Golang :rat: is updated to 1.24 OpenJDK :coffee: versions 24 GA and 25 early access snapshot are now available OpenJDK OpenJDK 21 is still the default. OpenJDK 24 is included as an optional OpenJDK. An early access snapshot of OpenJDK 25 is also included. Support for OpenJDK LTS versions 17, 11 and 8 is being maintained. OpenJDK with CRaC versions 17 and 21 also continue to be supported. We are excited to announce the devpack-for-spring 19 snap and a set of Spring® content snaps 7 that will serve as development tools for Spring® projects. Developers can now quickly build Ubuntu ROCK images for their Java applications using the Gradle and Maven plugins for Rockcraft 16. Additionally, GraalVM Community Edition for JDK versions 21, 24 and 25ea is now available as a snap 4. Java developers now have a choice to build and deploy their applications with standard OpenJDK, with OpenJDK-CRaC or as a GraalVM native image. .NET .NET versions 8 and 9 continue to be supported. The dotnet 20 snap is updated to include .NET version 9. The powershell-preview 19 snap has been updated to build from source.