Need freezer cgroup - safe to set kernel option?


Jul 8, 2018
HI all,
I'm using JipHop's Jailmaker and I sometimes use jails to test new cluster compute software. This uses slurm as the job manager, which in turn depends on the freezer cgroup, which it uses through /sys/fs/cgroup/freezer. The freezer cgroup however is only exposed with the kernel cmdline parameter "systemd.unified_cgroup_hierarchy=0". As this is a needed inside a jail, as I understand it this parameter would have to be set in the underlying TrueNAS kernel. Is it safe to do so or does TrueNAS use te cgroup hierarchy in ways that are incompatible with that kernel cmdline option? Am hesitant to just go try as this machine is headless, in a rack, and booting issues are therefore a bit of a hassle.