After discussions here:
https://lists.freedesktop.org/archives/systemd-devel/2022-July/thread.html
EOY 2023 is apparently what people can agree with, hence let formalize
this in the TODO list, so we don't forget.
systemd System and Service Manager
+CHANGES WITH 252:
+
+ Announcement of Future Feature Removal
+
+ * Please note that we intend to remove cgroupsv1 support from systemd
+ release after EOY 2023. If you run services that make explicit use of
+ cgroupsv1 features, please implement compatibility with cgroupsv2
+ sooner rather than later, if you haven't done so yet. Most of Linux
+ userspace has been ported over already.
+
CHANGES WITH 251:
Backwards-incompatible changes:
Features:
+* remove cgrouspv1 support EOY 2023. As per
+ https://lists.freedesktop.org/archives/systemd-devel/2022-July/048120.html
+ and then rework cgroupsv2 support around fds, i.e. keep one fd per active
+ unit around, and always operate on that, instead of cgroup fs paths.
+
* add small wrapper around qemu that implements sd_notify/AF_VSOCK + machined and
maybe some other stuff and boots it