Kernel and System Libraries
The following notable features, enhancements, and changes apply to the Red Hat Compatible Kernel (RHCK) that's shipped with the current Oracle Linux 9 version.
View cgroup Instances
With the introduction of cgroup v2, the traditional method of viewing
cgroup instances using the /proc/cgroups file is no longer applicable.
The /proc/cgroups file, designed for cgroup v1, is
deprecated for cgroup v2 as it doesn't provide the correct
information.
To accurately find the number of cgroup subsystems with cgroup v2, you
can now use the cgroup.stat file in the root cgroup. This file serves
as the replacement for /proc/cgroups in cgroup v2,
providing the correct count of cgroup subsystems.