Comment 9 for bug 1769309

Same problem here after upgrading to kernel 4.5.0-24.26:

user@machine:~$ sudo systemd-analyze blame
    7min 50.750s plymouth-quit-wait.service
    6min 17.955s snapd.seeded.service
         15.700s snapd.service
          6.253s NetworkManager-wait-online.service
          1.502s dev-mapper-ubuntu\x2d\x2dvg\x2droot.device
          1.231s dev-loop0.device
          1.223s dev-loop1.device
          1.203s dev-loop2.device
          1.182s dev-loop3.device
           737ms fwupd.service
           265ms networkd-dispatcher.service
           253ms NetworkManager.service
           244ms plymouth-start.service
           230ms apparmor.service
           223ms udisks2.service
           199ms ModemManager.service
           190ms keyboard-setup.service
           182ms systemd-logind.service
           177ms systemd-journal-flush.service
           173ms accounts-daemon.service
           168ms systemd-udev-trigger.service
           149ms systemd-rfkill.service
           132ms speech-dispatcher.service
           127ms apport.service
           125ms systemd-timesyncd.service
           123ms avahi-daemon.service
           122ms systemd-resolved.service
           112ms bluetooth.service
           109ms packagekit.service
           109ms systemd-journald.service
           106ms grub-common.service
            99ms lvm2-pvscan@8:1.service
            95ms lvm2-monitor.service
            93ms wpa_supplicant.service
            89ms upower.service
            85ms thermald.service
            81ms networking.service
            81ms pppd-dns.service
lines 1-38

However, interestingly, if I move mouse while booting, the output differs greatly:

user@machine:~$ sudo systemd-analyze blame
          6.294s NetworkManager-wait-online.service
          4.453s plymouth-quit-wait.service
          1.474s dev-mapper-ubuntu\x2d\x2dvg\x2droot.device
          1.257s dev-loop0.device
          1.246s dev-loop1.device
          1.227s dev-loop2.device
          1.204s dev-loop3.device
          1.060s snapd.service
           749ms fwupd.service
           410ms apparmor.service
           333ms networkd-dispatcher.service
           327ms udisks2.service
           255ms NetworkManager.service
           247ms plymouth-start.service
           216ms ModemManager.service
           199ms systemd-rfkill.service
           195ms accounts-daemon.service
           190ms systemd-journal-flush.service
           168ms systemd-logind.service
           157ms systemd-timesyncd.service
           154ms keyboard-setup.service
           150ms systemd-resolved.service
           137ms systemd-udev-trigger.service
           122ms thermald.service
           110ms grub-common.service
           109ms avahi-daemon.service
           106ms wpa_supplicant.service
           103ms systemd-journald.service
           102ms apport.service
           102ms bluetooth.service
            97ms packagekit.service
            94ms networking.service
            93ms upower.service
            90ms lvm2-pvscan@8:1.service
            90ms lvm2-monitor.service
            83ms gpu-manager.service