Hi Martin, The ssh session controller here is different from yours:
$ egrep 'systemd|pids' /proc/self/cgroup 11:pids:/system.slice/ssh.service 1:name=systemd:/system.slice/ssh.service $ cat /sys/fs/cgroup/pids/system.slice/pids.max max $ cat /sys/fs/cgroup/pids/system.slice/ssh.service/pids.max 512 Here are the evidences you requested (journal.txt is attached above this comment): $ cat /proc/self/cgroup 11:perf_event:/ 10:blkio:/ 9:memory:/ 8:net_cls,net_prio:/ 7:freezer:/ 6:cpuset:/ 5:cpu,cpuacct:/ 4:devices:/system.slice/ssh.service 3:hugetlb:/ 2:pids:/system.slice/ssh.service 1:name=systemd:/system.slice/ssh.service No error messages in "sudo journalctl -t sshd": $ sudo journalctl -t sshd -l -- Logs begin at Wed 2016-03-30 09:55:43 BRT, end at Wed 2016-03-30 10:01:01 BRT. -- Mar 30 09:55:44 gromero2 sshd[1902]: Server listening on 0.0.0.0 port 22. Mar 30 09:55:44 gromero2 sshd[1902]: Server listening on :: port 22. Mar 30 09:57:29 gromero2 sshd[1942]: Accepted publickey for gromero from 192.168.122.1 port 46308 ssh2: RSA SHA256:KD/WZk56NzE26ubz6Aw8LE1RdJfeQlRzJ36wwYHyE0c Mar 30 09:57:29 gromero2 sshd[1942]: pam_unix(sshd:session): session opened for user gromero by (uid=0) $XDG_SESSION_ID is unset, echo $XDG_SESSION_ID shows nothing. $ sudo journalctl -t systemd-logind -- Logs begin at Wed 2016-03-30 09:55:43 BRT, end at Wed 2016-03-30 10:03:34 BRT. -- Mar 30 09:55:44 gromero2 systemd-logind[1780]: New seat seat0. $ loginctl SESSION UID USER SEAT 0 sessions listed. $ loginctl show-session $XDG_SESSION_ID EnableWallMessages=no NAutoVTs=6 KillExcludeUsers=root KillUserProcesses=no RebootToFirmwareSetup=no IdleHint=yes IdleSinceHint=0 IdleSinceHintMonotonic=0 InhibitDelayMaxUSec=5s HandlePowerKey=poweroff HandleSuspendKey=suspend HandleHibernateKey=hibernate HandleLidSwitch=suspend HandleLidSwitchDocked=ignore HoldoffTimeoutUSec=30s IdleAction=ignore IdleActionUSec=30min PreparingForShutdown=no PreparingForSleep=no Docked=no Thank you! -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1561658 Title: ppc64el ssh sessions don't run in session cgroup but in sshd's Status in systemd package in Ubuntu: Incomplete Bug description: 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 │ └─[email protected] │ ├─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 ├─[email protected] │ └─1833 /sbin/dhclient ├─accounts-daemon.service │ └─1717 /usr/lib/accountsservice/accounts-daemon ├─system-serial\x2dgetty.slice │ └─[email protected] │ └─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. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1561658/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
