I'm very new to Ubuntu.
My PC has had very slow boot and shut down times (for 2 days), I reduced the shut down time with this tutorial (https://sites.google.com/site/installationubuntu/home/ubuntu-16-4-lts/make-slow-shutdown-faster) but PC still has some latency problem.
systemd-analyze blame from the terminal shows:
17.990s NetworkManager-wait-online.service 7.379s dev-sda1.device 5.271s dev-loop0.device 5.268s dev-loop1.device 5.264s dev-loop2.device 4.067s snapd.service 2.015s postfix@-.service 1.909s plymouth-quit-wait.service 1.467s udisks2.service 1.291s fwupd.service 1.248s networking.service 536ms accounts-daemon.service 447ms tlp.service 433ms ModemManager.service 407ms NetworkManager.service 357ms lm-sensors.service 349ms keyboard-setup.service 339ms preload.service 339ms apparmor.service 333ms grub-common.service 333ms mono-xsp4.service 312ms systemd-logind.service 304ms apport.service
I think there is a problem but I don't know how to fix it.