I had a problem with app-emulation/docker-18.09.9 failing to start under sys-apps/systemd-243-r2. Errors in docker log were: level=warning msg="Your kernel does not support cgroup memory limit" level=warning msg="Unable to find cpu cgroup in mounts" level=warning msg="Unable to find blkio cgroup in mounts" level=warning msg="Unable to find cpuset cgroup in mounts" level=warning msg="mountpoint for pids not found" Error starting daemon: Devices cgroup isn't mounted It took me a while to find the solution, which is to enable cgroup-hybrid use flag of sys-apps/systemd. This solution is documented in https://wiki.gentoo.org/wiki/Docker, but it's really hard to find: wiki does not cite exact error message, so it's does not appear among results when googling for the error message. Is it possible to make docker ebuild require cgroup-hybrid use flag on systemd so that portage could enforce it automatically and users don't have to figure this out themselves after facing docker startup errors? I see in https://bugs.gentoo.org/699442 that app-emulation/libvirt already has such check.
*** This bug has been marked as a duplicate of bug 691844 ***
