Windows 10 启动需要 12/15 秒，而 Ubuntu 20.04 启动需要 40/45 秒。这两个操作系统都安装在三星 840 EVO SSD 上。
我已经提前为您提供了一些命令的输出（但请向我建议其他有用的命令）。
提前致谢。
以下是来自systemd-analyze 链：
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 @10.465s
└─multi-user.target @10.465s
└─kerneloops.service @8.657s +10ms
└─network-online.target @8.651s
└─NetworkManager-wait-online.service @3.343s +5.308s
└─NetworkManager.service @3.171s +170ms
└─dbus.service @3.169s
└─basic.target @3.159s
└─sockets.target @3.159s
└─snapd.socket @3.158s +673us
└─sysinit.target @3.153s
└─snapd.apparmor.service @2.779s +106ms
└─apparmor.service @2.660s +118ms
└─local-fs.target @2.659s
└─run-user-125-gvfs.mount @3.864s
└─run-user-125.mount @3.651s
└─local-fs-pre.target @343ms
└─systemd-tmpfiles-setup-dev.service @311ms +31ms
└─systemd-sysusers.service @284ms +26ms
└─systemd-remount-fs.service @269ms +12ms
└─systemd-journald.socket @260ms
└─-.mount @257ms
└─system.slice @257ms
└─-.slice @257ms
以下是来自systemd-analyze 责备：
7.103s plymouth-quit-wait.service
5.308s NetworkManager-wait-online.service
2.302s snap-core20-975.mount
2.262s snap-snapd-11841.mount
2.256s snap-youtube\x2ddl-3805.mount
2.187s snap-skype-173.mount
2.124s snap-snap\x2dstore-518.mount
2.080s dev-sda2.device
2.060s snap-pdftk-9.mount
1.952s snap-snap\x2dstore-498.mount
1.947s snap-spotify-46.mount
1.862s snap-telegram\x2ddesktop-2637.mount
1.825s snap-gtk\x2dcommon\x2dthemes-1514.mount
1.805s snap-spotify-45.mount
1.780s snap-gnome\x2d3\x2d34\x2d1804-60.mount
1.631s snap-gnome\x2d3\x2d34\x2d1804-66.mount
1.620s snap-pinta\x2djames\x2dcarroll-8.mount
1.619s snap-snapd-11588.mount
1.617s snap-skype-172.mount
1.573s snap-gnome\x2d3\x2d28\x2d1804-145.mount
1.565s snap-intellij\x2didea\x2dultimate-295.mount
1.546s snap-telegram\x2ddesktop-2619.mount
1.446s dev-loop2.device
1.370s dev-loop3.device
1.346s snap-postman-132.mount
1.336s snap-core18-1997.mount
1.336s dev-loop4.device
1.310s snap-postman-133.mount
1.220s snap-kde\x2dframeworks\x2d5\x2dqt\x2d5\x2d14\x2dcore18-4.mount
1.217s snap-pinta\x2djames\x2dcarroll-6.mount
1.158s snapd.service
1.144s snap-acestreamplayer-11.mount
1.131s snap-datagrip-107.mount
1.122s systemd-backlight@backlight:intel_backlight.service
1.118s dev-loop5.device
1.097s dev-loop0.device
1.051s dev-loop8.device
1.003s dev-loop1.device
999ms dev-loop6.device
978ms dev-loop7.device
908ms dev-loop9.device
855ms dev-loop11.device
852ms dev-loop10.device
814ms fwupd.service
615ms dev-loop12.device
555ms snap-intellij\x2didea\x2dultimate-289.mount
552ms snap-kde\x2dframeworks\x2d5\x2dqt\x2d5\x2d15\x2dcore20-14.mount
518ms networkd-dispatcher.service
491ms plymouth-read-write.service
488ms dev-loop14.device
483ms snap-code-64.mount
476ms snap-core20-1026.mount
440ms snap-gtk\x2dcommon\x2dthemes-1515.mount
437ms udisks2.service
435ms snapd.seeded.service
431ms snap-code-65.mount
415ms snap-gtk2\x2dcommon\x2dthemes-13.mount
395ms upower.service
360ms dev-loop16.device
349ms snap-datagrip-106.mount
342ms systemd-logind.service
322ms snap-core-11081.mount
291ms systemd-rfkill.service
283ms dev-loop17.device
276ms dev-loop20.device
229ms accounts-daemon.service
223ms systemd-fsck@dev-disk-by\x2duuid-8732e59a\x2d2720\x2d48f9\x2dafaf\x2d206471a8ed59.service
223ms systemd-journal-flush.service
218ms systemd-udevd.service
196ms dev-loop25.device
194ms dev-loop13.device
192ms systemd-resolved.service
192ms dev-loop15.device
192ms dev-loop19.device
171ms avahi-daemon.service
170ms NetworkManager.service
170ms bluetooth.service
165ms polkit.service
165ms dev-loop31.device
161ms snap-core18-2066.mount
157ms dev-loop30.device
155ms systemd-timesyncd.service
146ms switcheroo-control.service
141ms thermald.service
139ms wpa_supplicant.service
137ms dev-loop27.device
134ms dev-loop26.device
133ms dev-loop18.device
127ms systemd-journald.service
124ms systemd-udev-trigger.service
118ms apparmor.service
114ms [email protected]
113ms gpu-manager.service
112ms [email protected]
109ms snap-core-10958.mount
106ms snapd.apparmor.service
103ms dev-loop33.device
102ms dev-loop24.device
98ms apt-daily-upgrade.service
96ms dev-loop28.device
92ms apache2.service
88ms geoclue.service
81ms grub-common.service
74ms ModemManager.service
73ms keyboard-setup.service
70ms apport.service
69ms dev-loop32.device
59ms dev-loop23.device
56ms systemd-fsck@dev-disk-by\x2duuid-DD37\x2dA40E.service
55ms dev-loop22.device
55ms dev-loop21.device
53ms systemd-random-seed.service
51ms e2scrub_reap.service
47ms systemd-sysctl.service
41ms rsyslog.service
40ms colord.service
39ms grub-initrd-fallback.service
39ms gdm.service
34ms systemd-tmpfiles-clean.service
31ms systemd-tmpfiles-setup-dev.service
30ms dev-loop35.device
26ms systemd-tmpfiles-setup.service
26ms systemd-sysusers.service
23ms systemd-modules-load.service
21ms plymouth-start.service
19ms home.mount
19ms [email protected]
17ms nvidia-persistenced.service
15ms [email protected]
14ms pppd-dns.service
14ms [email protected]
13ms dev-hugepages.mount
12ms systemd-remount-fs.service
12ms dev-mqueue.mount
11ms sys-kernel-debug.mount
11ms sys-kernel-tracing.mount
10ms kerneloops.service
10ms boot-efi.mount
9ms alsa-restore.service
8ms systemd-update-utmp.service
8ms kmod-static-nodes.service
8ms systemd-user-sessions.service
7ms systemd-update-utmp-runlevel.service
5ms openvpn.service
5ms dev-loop36.device
4ms console-setup.service
3ms rtkit-daemon.service
3ms sys-fs-fuse-connections.mount
3ms ufw.service
2ms setvtrgb.service
2ms sys-kernel-config.mount
1ms dev-loop29.device
673us snapd.socket
以下是来自systemd-分析
Startup finished in 3.289s (firmware) + 7.828s (loader) + 35.232s (kernel) + 12.593s (userspace) = 58.943s
graphical.target reached after 12.583s in userspace
内核日志（dmesg）： https://drive.google.com/file/d/1Rxr-TZuYXvwSyRz-PQkBW4iiNf5dKUL3/view?usp=sharing
答案1
和一些评论者一样，我建议你用 .deb 版本替换所有 snap。这应该会显著缩短你的启动时间。你实际上并不需要使用 sudo apt install 来实现这一点。
也许和你一样，我更喜欢通过 Ubuntu 软件进行图形安装。每当你想从那里安装某些东西时，请检查右上角。应该有一个下拉菜单，上面有“ubuntu-focal-SOMETHING”或“latest/stable”等字样。如果是前者，你就可以开始了：.deb 包将被安装。如果是后者，那么这是一个 Snap 包，我建议你选择任何“ubuntu-focal-SOMETHING”选项。
如果 Ubuntu 软件中只有 Snap 选项，您可以随时转到您喜欢的软件的网站页面并直接从那里下载 .deb 包。安装此包还会将您连接到该应用程序的官方 PPA，从而启用自动更新。这就是您可以获取 Skype 和 Spotify 应用程序的 .deb 包的方法。Telegram 在 Ubuntu 软件中以 .deb 形式提供。您可以自己查看 Pinta。至于 YouTube 应用程序，它可能只是桌面包装器中的网站，因此您可以考虑在 Firefox 中观看 YouTube，或者获取网站包装器应用程序 .deb 包。但这是另一个问题。
希望这可以帮助！