Gfilui

I am using Ubuntu 18.04 on a HP laptop dual booted with Windows 10, with 40 GB of disk space for Ubuntu and a 20 GB of SWAP area since I have an 8 GB of RAM.
I am using a HDD. Out of the 40 GB, 32.5 GB is still available and free. I have freshly installed the OS a few weeks back.
The shutdown time is really short, say 5 seconds, but the time it takes to boot up goes up to 1 minute.
I have edited /etc/initramfs-tools/initramfs.conf and changed MODULES=dep.
This has greatly reduced time taken by initramfs.
I'm not sure how else to improve it and reduce the time taken.

Boot time from systemd-analyze blame:

 23.512s dev-sda6.device
 21.462s plymouth-quit-wait.service
 18.832s systemd-udevd.service
 18.395s apparmor.service
 17.486s systemd-tmpfiles-setup.service
 6.801s NetworkManager-wait-online.service
 6.732s plymouth-start.service
 5.873s plymouth-read-write.service
 4.169s udisks2.service
 3.890s networking.service
 3.889s accounts-daemon.service
 3.013s speech-dispatcher.service
 2.573s networkd-dispatcher.service
 2.527s NetworkManager.service
 2.453s avahi-daemon.service
 2.449s thermald.service
 2.446s alsa-restore.service
 2.446s systemd-logind.service
 2.443s pppd-dns.service
 2.438s gpu-manager.service
 2.434s rsyslog.service
 2.016s apport.service
 1.426s wpa_supplicant.service
 1.388s dns-clean.service
 1.276s grub-common.service
 1.269s keyboard-setup.service
 1.056s tlp.service
 1.007s systemd-random-seed.service
 987ms packagekit.service
 896ms fwupd.service
 878ms systemd-tmpfiles-setup-dev.service
 779ms systemd-remount-fs.service
 758ms dev-mqueue.mount
 714ms sys-kernel-debug.mount
 712ms dev-hugepages.mount
 694ms systemd-modules-load.service
 590ms polkit.service
 579ms iio-sensor-proxy.service
 574ms systemd-sysctl.service
 442ms colord.service
 434ms systemd-journal-flush.service
 379ms systemd-timesyncd.service
 332ms dev-disk-byx2duuid-72e62aa6x2deefax2d49e1x2daba3x2d858b0e7dfbd3.swap
 330ms upower.service
 321ms systemd-journald.service
 312ms systemd-backlight@backlight:intel_backlight.service
 230ms setvtrgb.service
 217ms ufw.service
 209ms user@1000.service
 179ms systemd-resolved.service
 174ms bolt.service
 141ms gdm.service
 106ms kmod-static-nodes.service
 87ms console-setup.service
 73ms systemd-update-utmp.service
 56ms systemd-udev-trigger.service
 52ms kerneloops.service
 22ms systemd-user-sessions.service
 20ms sys-fs-fuse-connections.mount
 19ms rtkit-daemon.service
 19ms sys-kernel-config.mount
 8ms systemd-update-utmp-runlevel.service

free --human:

 total used free shared buff/cache available
Mem: 7.7G 1.2G 5.4G 148M 1.1G 6.3G
Swap: 19G 0B 19G

Output of ls /etc/apparmor.d/:

abstractions force-complain tunables usr.bin.man usr.lib.libreoffice.program.soffice.bin usr.sbin.cupsd usr.sbin.tcpdump
cache local usr.bin.evince usr.lib.libreoffice.program.oosplash usr.lib.libreoffice.program.xpdfimport usr.sbin.ippusbxd
disable sbin.dhclient usr.bin.firefox usr.lib.libreoffice.program.senddoc usr.sbin.cups-browsed usr.sbin.rsyslogd

NOTE:

• In order to improve the time taken by systemd-journal-flush.service I have reduced the MAX file size the journal flush service uses to 50M.


• sda6 is the partition where I have installed Ubuntu on my HDD


• I do not use Thunderbolt on my machine


• I don't use SSD

EDIT: Added benchmark results

sudo hdparm -Tt /dev/sda :

/dev/sda:
 Timing cached reads: 11730 MB in 2.00 seconds = 5876.89 MB/sec
 Timing buffered disk reads: 322 MB in 3.00 seconds = 107.22 MB/sec

sudo hdparm -v /dev/sda :

/dev/sda:
 multcount = 16 (on)
 IO_support = 1 (32-bit)
 readonly = 0 (off)
 readahead = 256 (on)
 geometry = 121601/255/63, sectors = 1953525168, start = 0

dd if=/dev/zero of=/tmp/output bs=8k count=10k; rm -f /tmp/output :

10240+0 records in
10240+0 records out
83886080 bytes (84 MB, 80 MiB) copied, 0.0681511 s, 1.2 GB/s

Graphical Results Image Here