Fedora 26 uses grub2 as default boot loader , and traditional sequential init daemon is replaced by systemd start up daemon which can start servuce simultaneously.
there are situations where boot times are longer than expected.
Best way is to start analying the time taken by the process to start this can be checked by systemctl-analyze
comamnd.
#systemd-analyze Startup finished in 2.685s (kernel) + 6.928s (initrd) + 1min 4.830s (userspace) = 2min 13.443s
The same above can be exported as an image and boot times can be investigated
#systemd-analyze plot > boot.svg
#systemd-analyze blame
37.894s abrtd.service
25.961s docker.service
18.333s tuned.service
14.288s plymouth-quit-wait.service
12.432s sssd.service
10.672s libvirtd.service
10.296s firewalld.service
9.284s NetworkManager-wait-online.service
7.816s lvm2-monitor.service
6.750s systemd-udev-settle.service
4.856s dev-sdb3.device
4.565s udisks2.service
4.276s polkit.service
4.013s initrd-switch-root.service
3.485s systemd-journal-flush.service
2.941s gssproxy.service
2.520s rsyslog.service
2.520s netcf-transaction.service
2.477s ModemManager.service
2.045s lightdm.service
1.921s dracut-initqueue.service
1.669s systemd-fsck-root.service
1.622s nagios.service
1.596s avahi-daemon.service
1.544s chronyd.service
1.461s thermald.service
1.428s systemd-vconsole-setup.service
1.300s fedora-readonly.service
1.226s sshd.service
1.203s bluetooth.service
1.123s proc-sys-fs-binfmt_misc.mount
1.107s systemd-tmpfiles-setup-dev.service
1.072s sysstat.service
1.060s dnf-makecache.service
1.056s systemd-udevd.service
844ms lm_sensors.service
802ms tmp.mount
744ms livesys.service
736ms rtkit-daemon.service
712ms switcheroo-control.service
679ms NetworkManager.service
648ms accounts-daemon.service
599ms upower.service
596ms systemd-user-sessions.service
560ms dev-mqueue.mount
509ms wpa_supplicant.service
499ms systemd-remount-fs.service
495ms auditd.service
459ms tlp.service
from the above we can see that abrtd , sssd services are taking longer duration during boot.
abrtd is a crash reporting tool it is safe to disable this service if you dont want to have crash reporting enabled.
#systemctl stop abrtd #systemctl disable abrtd
sssd service is mainly used for remote directory authentication like ldap , freeIpa services if you are not using ldap its safe to disable the service.
#systemctl stop sssd.service #systemctl disable sssd.service Removed /etc/systemd/system/multi-user.target.wants/sssd.service
We can even use systemd-analyze critical-chain to see the boot chain process
systemd-analyze critical-chain
The time after the unit is active or started is printed after the “@” character.
The time the unit takes to start is printed after the “+” character.
$systemd-analyze
graphical.target @1min 4.366s
└─multi-user.target @1min 4.366s
└─docker.service @38.404s +25.961s
└─network-online.target @38.396s
└─NetworkManager-wait-online.service @29.109s +9.284s
└─NetworkManager.service @27.559s +679ms
└─network-pre.target @27.556s
└─firewalld.service @17.259s +10.296s
└─polkit.service @12.820s +4.276s
└─basic.target @12.658s
└─sockets.target @12.658s
└─cockpit.socket @12.614s +43ms
└─sysinit.target @12.558s
└─systemd-update-utmp.service @12.523s +33ms
└─auditd.service @12.025s +495ms
└─systemd-tmpfiles-setup.service @11.648s +361ms
└─fedora-import-state.service @11.448s +197ms
└─local-fs.target @11.440s
└─var-lib-docker-plugins.mount @52.068s
└─local-fs-pre.target @11.006s
└─lvm2-monitor.service @3.189s +7.816s
└─lvm2-lvmetad.service @10.667s
└─lvm2-lvmetad.socket @3.184s
└─-.mount
└─system.slice
└─-.slice
Analyzing boot time after disabling services.
#systemd-analyze Startup finished in 2.701s (kernel) + 5.342s (initrd) + 1min 12.818s (userspace) = 1min 20.861s