Any steps needed to setup TRIM for SSD

[GreyGeek]

It seems Kubuntu 18.04 also automatically added fstrim.service to my system.

specialed@specialed-Aspire-VN7-791:~$ dpkg -L util-linux|grep fstrim
/lib/systemd/system/fstrim.service
/lib/systemd/system/fstrim.timer
/sbin/fstrim
/usr/share/bash-completion/completions/fstrim
/usr/share/man/man8/fstrim.8.gz

This runs every time I boot the machine. The problem is it adds 15 seconds to my boot time.

specialed@specialed-Aspire-VN7-791:~$ systemd-analyze blame         
        15.071s fstrim.service
         7.953s NetworkManager-wait-online.service
         1.783s apt-daily-upgrade.service
         1.324s networkd-dispatcher.service
         1.192s gpu-manager.service
         1.154s snapd.service
          748ms mpd.service
          660ms NetworkManager.service
          647ms apt-daily.service
          612ms motd-news.service
          538ms colord.service
          520ms dev-sdb1.device
          470ms systemd-user-sessions.service
          403ms virtualbox.service
          263ms udisks2.service
          217ms systemd-logind.service
          200ms ModemManager.service
          183ms systemd-resolved.service
          180ms grub-common.service
          172ms systemd-timesyncd.service
          148ms systemd-udevd.service
          147ms apparmor.service
          129ms systemd-journal-flush.service
          128ms systemd-rfkill.service
          127ms upower.service
          123ms wpa_supplicant.service
          110ms accounts-daemon.service
           93ms alsa-restore.service
           77ms keyboard-setup.service
           76ms apport.service
           70ms systemd-udev-trigger.service
           68ms plymouth-quit.service
           65ms rsyslog.service
           56ms polkit.service
           55ms thermald.service
           53ms swapfile.swap
           45ms systemd-journald.service

I'd prefer to remove the service on boot and change it to a cron job or even do it manually. Also the 7.953s NetworkManager-wait-online.service adds almost 8 seconds to my boot times too. Can I remove that? If so how?

How much time it adds depends on how much it has to trim. This morning my fstrim, which is set to run weekly and 30 min after bootup, took 43 seconds. Apt-daily-upgrade.timer is another one that causes delays during bootup.

You can delay fstrim from running during the bootup by putting
RandomizedDelaySec=30min
into the timer section of
/etc/systemd/system/timers.target.wants/fstrim.timer

You can do the same thing with
/etc/systemd/system/timers.target.wants/apt-daily-upgrade.timer

and putting
RandomizedDelaySec=1h
into
/etc/systemd/system/timers.target.wants/apt-daily.timer

[SpecialEd]

Thanks GG, I'll give it a try.