我在笔记本电脑上安装了 ubuntu 20.04 lts，它配备了 i7 第 9 代 CPU 和 16 GB 内存。但启动速度非常慢，需要 2-3 分钟。有人能帮我解决这个问题吗？
这是 systemd-analyze blame 命令的输出：50.020s plymouth-quit-wait.service
25.936s man-db.service
20.932s snapd.service
20.105s apt-daily-upgrade.service
19.116s systemd-journal-flush.service
17.071s networkd-dispatcher.service
14.753s gpu-manager.service
13.553s udisks2.service
13.362s dev-sda6.device
10.847s NetworkManager-wait-online.service
9.808s accounts-daemon.service
7.885s dev-loop4.device
7.688s dev-loop9.device
7.478s dev-loop19.device
7.374s dev-loop15.device
7.159s dev-loop17.device
7.030s logrotate.service
6.893s polkit.service
6.878s avahi-daemon.service
6.872s bluetooth.service
6.869s NetworkManager.service
6.386s apport-autoreport.service
6.302s dev-loop13.device
1-23 行