What must I do with the systemd-analyze critical chain informations

[lolo75]

Hello,

Very slow start, over 3 minutes...

=> cmd: sudo systemd-analyze time

Startup finished in 37.291s (kernel) + 2min 23.334s (userspace) = 3min 625ms
graphical.target reached after 2min 23.280s in userspace


After read many answers on the same slow start subjects, try few solutions without succes.

=> cmd: sudo systemd-analyze critical chain

graphical.target @2min 23.280s
└─lightdm.service @2min 22.412s +867ms
  └─systemd-user-sessions.service @56.566s +494ms
    └─network.target @56.562s
      └─NetworkManager.service @40.913s +15.648s
        └─dbus.service @32.538s
          └─basic.target @31.724s
            └─sockets.target @31.724s
              └─snapd.socket @31.553s +170ms
                └─sysinit.target @31.532s
                  └─snapd.apparmor.service @31.466s +64ms
                    └─apparmor.service @17.074s +14.228s
                      └─local-fs.target @17.021s
                        └─local-fs-pre.target @16.467s
                          └─keyboard-setup.service @6.033s +10.433s
                            └─systemd-journald.socket @6.000s
                              └─system.slice @5.999s
                                └─-.slice @5.109s

=> cmd: sudo systemd-analyze blame

    1min 50.318s vboxadd.service
    1min 26.211s plymouth-quit-wait.service
        43.699s resolvconf-pull-resolved.service
        36.044s dev-sda1.device
        23.630s udisks2.service
        23.536s mysql.service
        23.234s snapd.service
        22.225s networkd-dispatcher.service
        19.626s systemd-journal-flush.service
        15.648s NetworkManager.service
        15.449s accounts-daemon.service
        14.636s laptop-mode.service
        14.228s apparmor.service
        13.446s gpu-manager.service
        12.104s apport.service
        11.692s ModemManager.service
        11.525s devolonetsvc.service
        10.634s etc-setserial.service
        10.433s keyboard-setup.service
          9.958s lm-sensors.service
          9.685s [email protected]
          9.608s networking.service
          9.541s console-kit-log-system-start.service


So what seems the solution at your opinion ?

(haveged solution already tested without success)

Many thanks

Laurent

[Moltke]

lolo75[/member]]Very slow start, over 3 minutes...So what seems the solution at your opinion ?

Sometimes, most of times actually, the

Code:

systemd-analyze

output doesn't point the culprit of a "slow start", it just shows how much time each process takes to start but that doesn't neccesarily mean they're causing it, could be something else; old, low powered hardware, files system error and yes, it may be that one process is taking to long to start thus slowing down the whole boot up process. In your case,

Code:

vboxadd.service

seems to be taking too long to start, if you don't use virtualbox or don't need that service to start at boot, you can disable it

Code:

sudo systemctl stop vboxadd.service

enter your password when asked, hit enter, then do

Code:

sudo systemctl disable vboxadd.service

Reboot and check whether LL keeps starting slow or not.

Hope this helps!

[lolo75]

Hello Moltke,

Understood the informations coming from systemd-analyze time.
Done your advices

=> cmd systemd-analyze blame

1min 30.243s nmbd.service
        57.570s resolvconf-pull-resolved.service
        28.391s systemd-journal-flush.service
        27.938s dev-sda1.device
        24.810s mysql.service
        19.786s keyboard-setup.service
        17.993s ufw.service
        16.123s lvm2-monitor.service
        16.070s snapd.service
        15.289s systemd-modules-load.service
        15.232s systemd-tmpfiles-setup-dev.service
        14.623s [email protected]
        11.954s NetworkManager.service
        11.368s udisks2.service
        10.065s ModemManager.service
        10.027s NetworkManager-wait-online.service
          9.007s apparmor.service
          6.220s accounts-daemon.service
          4.621s networking.service
          4.454s console-kit-log-system-start.service
          4.393s lmt-poll.service
          4.379s rsyslog.service
          4.353s networkd-dispatcher.service
          4.241s grub-common.service
          3.478s lightdm.service
          3.472s plymouth-quit-wait.service

So results are faster boot. 

I now note than
- "vboxadd.service" has disappeared, as expected
- "plymouth-quit-wait.service" now takes 3.5 sec compared with 1min26...
- "nmbd.service" is now the longuest process with 1min 30sec...


Now, shutdown the computer and restart again...

Results are :

=> cmd sudo systemd-analyze time

Startup finished in 37.363s (kernel) + 1min 22.578s (userspace) = 1min 59.942s
graphical.target reached after 1min 22.505s in userspace

=> cmd sudo systemd-analyze blame

        42.724s resolvconf-pull-resolved.service
        32.790s mysql.service
        28.599s dev-sda1.device
        28.486s systemd-journal-flush.service
        20.695s snapd.service
        18.441s keyboard-setup.service
        17.515s ufw.service
        15.258s lvm2-monitor.service
        15.034s systemd-tmpfiles-setup-dev.service
        14.522s systemd-modules-load.service
        10.506s NetworkManager.service
          9.950s [email protected]
          8.839s ModemManager.service
          7.541s accounts-daemon.service
          7.013s apparmor.service
          5.669s smbd.service
          5.495s NetworkManager-wait-online.service
          5.437s rsyslog.service
          5.325s udisks2.service
          5.109s nmbd.service
          4.890s devolonetsvc.service
          4.681s systemd-resolved.service
          4.426s apport.service



See also : https://askubuntu.com/questions/1247213/...down-my-ub

and then : https://doc.ubuntu-fr.org/snap
specially the 5. and 6.


i.e with an other computer, i5-6200U @ 2.3GHz, same LL4.8 : kernel 4.259sec and userspace 40.5 sec...
Same order process : vboxadd.service 34 sec and plymouth-quit-wait.service for 33 sec then 6sec and less for all the others process...

Thanks

Laurent

[Moltke]

Hello Moltke,

Understood the informations coming from systemd-analyze time.
Done your advices

So results are faster boot. 

I now note than
- "vboxadd.service" has disappeared, as expected
- "plymouth-quit-wait.service" now takes 3.5 sec compared with 1min26...
- "nmbd.service" is now the longuest process with 1min 30sec...

i.e with an other computer, i5-6200U @ 2.3GHz, same LL4.8 : kernel 4.259sec and userspace 40.5 sec...
Same order process : vboxadd.service 34 sec and plymouth-quit-wait.service for 33 sec then 6sec and less for all the others process...

Thanks

Laurent

Do any of those computer have a SSD or a HDD? If a SSD then it should definitely start faster than that, if a HDD then it's likely normal since those tend to be slower. By the way, when pasting terminal output in the forum, try using bbcodes, just click on the symbol from the menu above, it helps readbility so it looks like this

Code:

systemd-analyze blame

1min 30.243s nmbd.service
         57.570s resolvconf-pull-resolved.service
         28.391s systemd-journal-flush.service
         27.938s dev-sda1.device
         24.810s mysql.service
         19.786s keyboard-setup.service
         17.993s ufw.service
         16.123s lvm2-monitor.service
         16.070s snapd.service
         15.289s systemd-modules-load.service
         15.232s systemd-tmpfiles-setup-dev.service
         14.623s [email protected]
         11.954s NetworkManager.service
         11.368s udisks2.service
         10.065s ModemManager.service
         10.027s NetworkManager-wait-online.service
          9.007s apparmor.service
          6.220s accounts-daemon.service
          4.621s networking.service
          4.454s console-kit-log-system-start.service
          4.393s lmt-poll.service
          4.379s rsyslog.service
          4.353s networkd-dispatcher.service
          4.241s grub-common.service
          3.478s lightdm.service
          3.472s plymouth-quit-wait.service

It's a lot nicer and easier to read