Have a dual-boot system (Ubuntu 22.04 and Win10) running on a Lenovo Thinkpad.
No issues with either until last week when booting into Ubuntu partition started to take ~10-15mins from typical 60s.
Was able to troubleshoot and identify that the issue arises when one of my 3 external HDs is connected to the laptop. Not seeing anything in /var/log/syslog, and have included output from the debugging commands I've seen mentioned. Not sure how useful as I removed the problem-causing HD to get into the system:
chris@chris-X1C6:~$ systemd-analyze blame
1min 40.340s fstrim.service
40.929s apt-daily-upgrade.service
26.476s plymouth-quit-wait.service
13.852s apt-daily.service
6.576s NetworkManager-wait-online.service
5.565s gpu-manager.service
5.252s plexmediaserver.service
4.819s plocate-updatedb.service
4.160s qemu-kvm.service
2.784s snapd.service
1.846s fwupd.service
1.436s systemd-backlight@backlight:intel_backlight.service
1.274s mysql.service
731ms systemd-fsck@dev-disk-by\x2duuid-0c2e04fe\x2d9691\x2d4db4\x2da0c1\x2dabc269f2460c.service
chris@chris-X1C6:~$ systemd-analyze critical-chain
The time when unit became active or started is printed after the "@" character.
The time the unit took to start is printed after the "+" character.
graphical.target @29.201s
└─multi-user.target @29.201s
└─plymouth-quit-wait.service @2.723s +26.476s
└─systemd-user-sessions.service @2.695s +14ms
└─network.target @2.643s
└─NetworkManager.service @2.269s +364ms
└─dbus.service @2.264s
└─basic.target @2.255s
└─sockets.target @2.255s
└─snapd.socket @2.237s +17ms
└─sysinit.target @2.231s
└─systemd-backlight@backlight:intel_backlight.service @6.069s +1.436s
└─system-systemd\x2dbacklight.slice @1.287s
└─system.slice @290ms
└─-.slice @290ms
