Ubuntu 20.04 的启动过程耗时太长。我想知道如何缩短启动时间。
这是我的硬件信息：
- 内存——4GB
- 磁盘类型 - HDD
- 磁盘空间 - 1TB
- 架构——amd64
- 处理器 - 英特尔（酷睿 i3）第 7 代
如果有任何其他所需信息，请评论，我会提供。
输出dmesg：
systemd-analyze输出：
Startup finished in 4.133s (firmware) + 5.169s (loader) + 5.074s (kernel) + 31min 12.092s (userspace) = 31min 26.470s
graphical.target reached after 3min 9.875s in userspace
systemd-anlyze blame输出 ：
30min 36.678s fstrim.service
2min 19.796s plymouth-quit-wait.service
33.670s snapd.service
31.615s networkd-dispatcher.service
28.168s udisks2.service
21.824s accounts-daemon.service
21.649s fwupd.service
16.696s systemd-tmpfiles-clean.service
16.168s ModemManager.service
15.824s dev-sda3.device
14.959s polkit.service
14.086s avahi-daemon.service
14.085s bluetooth.service
14.060s NetworkManager.service
14.049s dundee.service
14.018s ofono.service
13.795s switcheroo-control.service
13.787s thermald.service
13.782s wpa_supplicant.service
13.780s systemd-logind.service
10.643s systemd-tmpfiles-setup.service
9.122s [email protected]
9.110s plymouth-read-write.service
8.307s dev-loop11.device
8.275s dev-loop1.device
8.188s dev-loop8.device
7.778s dev-loop5.device
7.385s dev-loop10.device
7.307s dev-loop9.device
6.845s dev-loop3.device
6.568s dev-loop2.device
6.476s dev-loop4.device
6.474s dev-loop7.device
6.210s grub-common.service
6.074s apport.service
5.830s systemd-resolved.service
5.821s bolt.service
5.818s secureboot-db.service
5.184s gpu-manager.service
4.838s gdm.service
4.580s dev-loop6.device
4.534s dev-loop0.device
4.447s rsyslog.service
4.261s ubuntu-fan.service
3.503s apparmor.service
3.407s grub-initrd-fallback.service
2.575s snap-canonical\x2dlivepatch-95.mount
2.253s binfmt-support.service
2.234s snapd.apparmor.service
2.221s snap-chromium-1399.mount
2.050s e2scrub_reap.service
1.964s systemd-rfkill.service
1.873s snap-core-10185.mount
1.616s snap-core18-1932.mount
1.491s pppd-dns.service
1.478s colord.service
1.448s snapd.seeded.service
1.353s upower.service
1.333s snap-gnome\x2d3\x2d28\x2d1804-145.mount
1.181s systemd-backlight@backlight:intel_backlight.service
1.164s systemd-udevd.service
1.059s snap-gnome\x2d3\x2d34\x2d1804-60.mount
984ms systemd-fsck@dev-disk-by\x2duuid-565baeeb\x2df53c\x2d44c6\x2da9b3\x2d7604d7b7e16f.service
949ms systemd-modules-load.service
908ms apport-autoreport.service
828ms kerneloops.service
771ms systemd-random-seed.service
770ms openvpn.service
752ms [email protected]
749ms snap-gtk\x2dcommon\x2dthemes-1506.mount
725ms systemd-sysusers.service
675ms containerd.service
651ms systemd-udev-trigger.service
638ms virtualbox.service
628ms systemd-sysctl.service
608ms snap-kde\x2dframeworks\x2d5\x2dcore18-32.mount
600ms snap-simplescreenrecorder\x2dbrlin-69.mount
588ms systemd-fsck@dev-disk-by\x2duuid-2F60\x2d3524.service
538ms [email protected]
538ms ufw.service
530ms systemd-journald.service
513ms snap-slack-32.mount
467ms systemd-remount-fs.service
464ms qemu-kvm.service
414ms systemd-user-sessions.service
413ms console-setup.service
396ms plymouth-start.service
324ms systemd-tmpfiles-setup-dev.service
308ms systemd-timesyncd.service
268ms fam.service
255ms alsa-restore.service
236ms rtkit-daemon.service
227ms dev-hugepages.mount
226ms dev-mqueue.mount
224ms sys-kernel-debug.mount
223ms sys-kernel-tracing.mount
220ms kmod-static-nodes.service
204ms snap-snap\x2dstore-481.mount
195ms [email protected]
181ms setvtrgb.service
174ms dev-disk-by\x2duuid-628e5f66\x2dda0b\x2d41af\x2dbaca\x2dc4d1fafee694.swap
158ms systemd-update-utmp.service
144ms home.mount
138ms snap-snapd-9721.mount
124ms boot-efi.mount
44ms proc-sys-fs-binfmt_misc.mount
38ms systemd-update-utmp-runlevel.service
34ms [email protected]
5ms sys-fs-fuse-connections.mount
4ms sys-kernel-config.mount
2ms docker.socket
1ms snapd.socket
systemd-analyze critical-chain输出 ：
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 @3min 9.875s
└─multi-user.target @3min 9.875s
└─snapd.seeded.service @1min 9.328s +1.448s
└─snapd.service @35.652s +33.670s
└─basic.target @35.221s
└─sockets.target @35.221s
└─snapd.socket @35.219s +1ms
└─sysinit.target @35.071s
└─systemd-timesyncd.service @34.762s +308ms
└─systemd-tmpfiles-setup.service @24.029s +10.643s
└─local-fs.target @24.017s
└─run-snapd-ns-chromium.mnt.mount @12min 46.580s
└─run-snapd-ns.mount @57.339s
└─swap.target @23.033s
└─dev-disk-by\x2duuid-628e5f66\x2dda0b\x2d41af\x2dbaca\x2dc4d1fafee694.swap @22.857s +174ms
└─dev-disk-by\x2duuid-628e5f66\x2dda0b\x2d41af\x2dbaca\x2dc4d1fafee694.device @22.854s
cat /etc/fstab输出：
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda3 during installation
UUID=bc7f56e3-b60c-48a9-b04d-385d9c46c938 / ext4 errors=remount-ro 0 1
# /boot/efi was on /dev/sda1 during installation
UUID=2F60-3524 /boot/efi vfat umask=0077 0 1
# /home was on /dev/sda4 during installation
UUID=565baeeb-f53c-44c6-a9b3-7604d7b7e16f /home ext4 defaults 0 2
# swap was on /dev/sda2 during installation
UUID=628e5f66-da0b-41af-baca-c4d1fafee694 none swap sw 0 0
我已经检查了交换的 UUID。