Officially deprecate cgroup v1, but maintain it until May 2029 at least #51111
Description
Description
Most distros have already switched to cgroup v2, so I suggest officially deprecating cgroup v1, but maintaining it until the EOL of AlmaLinux 8 and Rocky Linux 8 (i.e., May 2029) at least.
The latest release in May 2029 does not necessarily need to support cgroup v1, but there should be at least one Maintained branch with the support for cgroup v1.
cgroup v1 distros
- Ubuntu 20.04
- "STANDARD SUPPORT": 2025-04-XX
- "UBUNTU PRO SUPPORT": 2030-04-XX
- "LEGACY SUPPORT": 2032-04-XX
- Red Hat Enterprise Linux 8
- "Full support": 2024-05-31
- "Maintenance support": 2029-05-31
- "ELS add-on": 2032-05-31
- Rocky Linux 8
- "Active Support": 2024-05-31
- "End of Life": 2029-05-31
- AlmaLinux 8
- "active support": 2024-05-31
- "security support": 2029-05-31
- Oracle Linux 8
- "Premier": 2029-07-XX
- "Extended": 2032-07-XX
- SUSE Linux Enterprise Server 15 SP5
- "General Support": 2024-12-31
- "LTSS": 2027-12-31
- Note: SP6 seems to have switched to cgroup v2
Testing cgroup v1
GitHub Actions have already stopped hosting cgroup v1 (Ubuntu 20.04), so Oracle Linux 8 (kernel 5.15) running in Lima is currently used for executing the integration tests with cgroup v1.
Lines 37 to 44 in b0c5090
Ideally the tests should be executed in AlmaLinux 8 or Rocky Linux 8 (kernel 4.18), but some tests are failing with them:
Discussion in other projects
- pid1: stop refusing to boot with cgroup v1 systemd/systemd#34999
- The support for cgroup v1 was disabled by default in systemd v256 (Jun 2024), and removed in systemd v258 (Sep 2025)
- [KEP-5573]: Remove cgroup v1 support kubernetes/enhancements#5574
- Proposal: synchronize cgroupv1 deprecation announcements opencontainers/runtime-spec#1251
It is expected (but not officially decided yet) that containerd supports cgroup v1 longer than Moby, and runc supports it longer than containerd.