自从几天前从 14.10 升级到 15.04 以来，grub OS 屏幕到登录屏幕的启动时间从 12 秒增加到大约 40 秒。这是我的systemd-analyze 关键链输出：
The time after the unit is active or started is printed after the "@" character.
The time the unit takes to start is printed after the "+" character.
graphical.target @37.433s
??multi-user.target @37.433s
??getty.target @37.432s
??getty@tty1.service @37.432s
??systemd-user-sessions.service @35.906s +9ms
??remote-fs.target @35.904s
??media-XalnasStorage.mount @35.849s +53ms
??network-online.target @35.846s
??network.target @11.636s
??NetworkManager.service @11.502s +132ms
??basic.target @11.487s
??sockets.target @11.487s
??avahi-daemon.socket @11.487s
??sysinit.target @11.485s
??networking.service @11.333s +65ms
??apparmor.service @11.269s +63ms
??local-fs.target …