Improving my Boot Time in Arch Linux

2020/08/22 by Paulo Pereira

~/categories/Linux ❯ #Linux #Arch Linux

I was investigating and issue with duplicity when I stumbled with systemd-analyze.

So I started to see what was contributing for my boot time and after that I started too see how to improved.

This is by no means a guide, but just what I changed to improve.

You can use sudo systemd-analyze blame to see load time for every programs that loads at boot time and sudo systemd-analyze critical-chain to basically see the critical programs that you could focus on.

The results, or how you interpret them depends on your system and what you need to load.

My critical-chain (before)

sudo systemd-analyze critical-chain

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 @19.908s
└─multi-user.target @19.908s
  └─cups-browsed.service @19.908s
    └─org.cups.cupsd.service @19.606s +299ms
      └─network-online.target @19.598s
        └─network.target @19.597s
          └─dhcpcd@eno1.service @2.841s +16.755s
            └─basic.target @2.828s
              └─sockets.target @2.827s
                └─snapd.socket @2.826s +792us
                  └─sysinit.target @2.820s
                    └─systemd-timesyncd.service @2.321s +498ms
                      └─systemd-tmpfiles-setup.service @2.210s +48ms
                        └─local-fs.target @2.203s
                          └─var-lib-snapd-snap-core18-1880.mount @1.603s +598ms
                            └─dev-loop10.device @2.200s +38ms

From this I saw 2 things to focus:

  1. I’m not really using snaps right now
  2. dhcpcd is taking 16s ou the 19s

Disabling ou removing programs you don’t need

By looking at your results, if you see something your are not really using you can disable the service ou remove the program.

In my case I removed snapd.

yay -Rns snapd

Replacing dhcpcd with systemd-networkd

Digging around I saw somebody suggesting using systemd-networkd instead of dhcpcd. I gave it a try.

I disabled the service (including NetworkManager):

sudo systemctl disable dhcpcd@eno1.service
sudo systemctl disable NetworkManager-wait-online
sudo systemctl disable NetworkManager

Also removed nm-applet from my startup list in i3.

# exec --no-startup-id nm-applet

Enabling systemd-networkd

As always check the wiki for more details.

You must create a configuration file for each of your network cards. In my case I’m only using a wired connection.

sudo vi /etc/systemd/network/20-wired.network

[Match]
Name=eno1

[Network]
DHCP=yes

And the enable the service:

sudo systemctl enable systemd-networkd
sudo systemctl enable systemd-resolved

I also installed a notification service:

yay -S networkd-notify-git

And added it to my i3 startup list:

exec --no-startup-id networkd-notify

My critical-chain (after)

It’s better for sure and I learned a few new things.

sudo systemd-analyze critical-chain

The time when unit became active or started is printed after>
The time the unit took to start is printed after the "+" cha>

graphical.target @9.564s
└─multi-user.target @9.564s
  └─cups-browsed.service @9.563s
    └─org.cups.cupsd.service @9.402s +159ms
      └─network-online.target @9.400s
        └─systemd-networkd-wait-online.service @1.533s +7.86>
          └─systemd-networkd.service @1.046s +484ms
            └─systemd-udevd.service @502ms +535ms
              └─systemd-tmpfiles-setup-dev.service @470ms +2>
                └─kmod-static-nodes.service @383ms +13ms
                  └─systemd-journald.socket @377ms
                    └─system.slice @367ms
                      └─-.slice @367ms