Public bug reported: On Ubuntu 16.04/ppc64el, the cgroup for a user session (bash) inherits from a sshd.service, when the user logs into the machine using SSH.
This causes the amount of process to be limited by /etc/systemd/system/conf DefaultTasksMax=512 This does not seem to happen on amd64. This is a cgroup tree diff: On x64, bash (in this case, PID 19405 ) spawned by sshd belongs to CGROUP session-5.scope->user-1003.slice->user.slice: └─user.slice ├─user-1000.slice │ ├─session-1.scope │ │ ├─634 sshd: brenohl [priv] │ │ ├─660 sshd: brenohl@pts/0 │ │ └─661 -bash │ └─user@1000.service │ ├─636 /lib/systemd/systemd --user │ └─637 (sd-pam) └─user-1003.slice ├─session-5.scope │ ├─19379 sshd: gromero [priv] │ ├─19404 sshd: gromero@pts/1 │ ├─19405 -bash However, in ppc64le, bash (in this case, PID 1913), spawned by sshd belongs to CGROUP ssh.service->system.slice->-.slice: -.slice ├─1720 /sbin/cgmanager -m name=systemd ├─init.scope └─system.slice ├─dbus.service │ └─1699 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation ├─cron.service │ └─1702 /usr/sbin/cron -f ├─ifup@eth0.service │ └─1833 /sbin/dhclient ├─accounts-daemon.service │ └─1717 /usr/lib/accountsservice/accounts-daemon ├─system-serial\x2dgetty.slice │ └─serial-getty@hvc0.service │ └─1875 /sbin/agetty --keep-baud 115200 38400 9600 hvc0 vt220 ├─systemd-journald.service │ └─1382 /lib/systemd/systemd-journald ├─systemd-timesyncd.service │ └─1639 /lib/systemd/systemd-timesyncd ├─ssh.service │ ├─1863 /usr/sbin/sshd -D │ ├─1897 sshd: gromero [priv] │ ├─1912 sshd: gromero@pts/0 │ ├─1913 -bash Having the user session associated with the systemd cgroups (/system.slice/ssh.service) instead of normal user/session cgroups (as user-XXXX.slice/session-5.scope), causes the process to be limited to the systemd TasksMax limit, thus, causing "Cannot fork" and "Resource temporary unavailable" problems when the amount of processes reaches this 512 limit. Gustavo Romero has more details about this problem, and will comment soon. ** Affects: systemd (Ubuntu) Importance: Undecided Assignee: Taco Screen team (taco-screen-team) Status: Confirmed ** Tags: ppc64el ** Changed in: systemd (Ubuntu) Assignee: (unassigned) => Taco Screen team (taco-screen-team) ** Changed in: systemd (Ubuntu) Status: New => Confirmed -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1561658 Title: “Cannot fork” and "Resource temporary unavailable" To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1561658/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs