我有 Ubuntu 18.04，启动时间很慢。
我已经运行了 systemd-analyze blame 和 critical chain，图片如下
5min 7.004s fstrim.service
1min 12.889s snapd.service
52.687s networkd-dispatcher.service
46.3995 lightdm.service
43.238s networking.service
38.646s ModemManager.service
35.840s dev-mmcblkOpl.device
34.086s apt-daily-upgrade.service
31.551s accounts-daemon.service
28.993s apport.service
28.070s pppd-dns.service
28.031s lm-sensors.service
27.801s teamviewerd.service
27.146s NetworkManager.service
23.254s motd-news.service
20.735s NetworkManager-watt-online.service
15.688s user@1000. service
10.275s udisks2.service
9.488s ssh.service
6.3055 systemd-journal-flush.service
graphical.target @1min 59.675s
multi-user.target @1min 59.675s
teamviewerd.service @1min 31.873 + 27.801s
network-online.target @1min 31.442s
NetworkManager-wait-online.service @1min 10.706 + 20.735s
NetwokrManager.service @37.790 + 27.146s
dbus.service @9.937s
basic.target @9.779s
看起来，似乎主要问题出在 fstrim 服务上？
先感谢您。