Ubuntu 如果插上显示器不使用，一段时间（通常是 20 分钟）后会突然停了。
目前我主要方案是这个： https://www.unixtutorial.org/disable-sleep-on-ubuntu-server/
主要信息：
禁止:
$ sudo systemctl mask sleep.target suspend.target hibernate.target hybrid-sleep.target Created symlink /etc/systemd/system/sleep.target → /dev/null. Created symlink /etc/systemd/system/suspend.target → /dev/null. Created symlink /etc/systemd/system/hibernate.target → /dev/null. Created symlink /etc/systemd/system/hybrid-sleep.target → /dev/null.
恢复:
$ sudo systemctl unmask sleep.target suspend.target hibernate.target hybrid-sleep.target Removed /etc/systemd/system/sleep.target. Removed /etc/systemd/system/suspend.target. Removed /etc/systemd/system/hibernate.target. Removed /etc/systemd/system/hybrid-sleep.target.
上面主要做法是把那几个 sleep, suspend, hibernate, hybrid-sleep 行为禁止掉了。
另外，考虑是不是装 Nvidia Driver 的时候不小心装上了 gnome 的缘故，所以做了如下设置。但是似乎不工作。
在当前用户检查电源管理 sleep-inactive-ac-timeout 设置:
$ gsettings get org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 1200
疑似这个就是原因。
修改成这样:
$ gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 0
查看目前所有选项如下：
$ gsettings list-recursively org.gnome.settings-daemon.plugins.power org.gnome.settings-daemon.plugins.power lid-close-ac-action 'suspend' org.gnome.settings-daemon.plugins.power time-critical 300 org.gnome.settings-daemon.plugins.power power-button-action 'suspend' org.gnome.settings-daemon.plugins.power lid-close-suspend-with-external-monitor false org.gnome.settings-daemon.plugins.power button-hibernate 'hibernate' org.gnome.settings-daemon.plugins.power idle-dim true org.gnome.settings-daemon.plugins.power button-power 'suspend' org.gnome.settings-daemon.plugins.power lid-close-battery-action 'suspend' org.gnome.settings-daemon.plugins.power priority 0 org.gnome.settings-daemon.plugins.power idle-brightness 30 org.gnome.settings-daemon.plugins.power active true org.gnome.settings-daemon.plugins.power critical-battery-action 'hibernate' org.gnome.settings-daemon.plugins.power button-suspend 'suspend' org.gnome.settings-daemon.plugins.power button-sleep 'hibernate' org.gnome.settings-daemon.plugins.power percentage-critical 3 org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 0 org.gnome.settings-daemon.plugins.power sleep-inactive-ac-type 'suspend' org.gnome.settings-daemon.plugins.power ambient-enabled true org.gnome.settings-daemon.plugins.power notify-perhaps-recall true org.gnome.settings-daemon.plugins.power percentage-low 10 org.gnome.settings-daemon.plugins.power percentage-action 2 org.gnome.settings-daemon.plugins.power sleep-inactive-battery-type 'suspend' org.gnome.settings-daemon.plugins.power time-low 1200 org.gnome.settings-daemon.plugins.power sleep-inactive-battery-timeout 1200 org.gnome.settings-daemon.plugins.power time-action 120 org.gnome.settings-daemon.plugins.power use-time-for-policy true
参考 https://ubuntu-mate.community/t/ubuntu-mate-auto-suspend-20-minutes-after-it-restart/17650
效果并没有变化，停止前 log 依然是，然后卡住。
Nov 24 18:50:09 diony NetworkManager[863]: <info> [1637751009.5098] manager: sleep: sleep requested (sleeping: no enabled: yes) Nov 24 18:50:09 diony ModemManager[934]: <info> [sleep-monitor] system is about to suspend Nov 24 18:50:09 diony NetworkManager[863]: <info> [1637751009.5100] manager: NetworkManager state is now ASLEEP Nov 24 18:50:09 diony gnome-shell[1286]: Screen lock is locked down, not locking Nov 24 18:50:09 diony systemd[1]: Reached target Sleep. Nov 24 18:50:09 diony systemd[1]: Starting Record successful boot for GRUB... Nov 24 18:50:09 diony systemd[1]: Starting Suspend... Nov 24 18:50:09 diony systemd-sleep[18784]: Suspending system... Nov 24 18:50:09 diony kernel: [ 1221.038239] PM: suspend entry (deep) Nov 24 18:50:09 diony systemd[1]: grub-common.service: Succeeded. Nov 24 18:50:09 diony systemd[1]: Finished Record successful boot for GRUB. Nov 24 18:50:09 diony systemd[1]: Starting GRUB failed boot detection... Nov 24 18:50:09 diony systemd[1]: grub-initrd-fallback.service: Succeeded. Nov 24 18:50:09 diony systemd[1]: Finished GRUB failed boot detection. Nov 24 18:50:09 diony kernel: [ 1221.097020] Filesystems sync: 0.058 seconds Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (**) Option "fd" "40" Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (II) event2 - Power Button: device removed Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (**) Option "fd" "43" Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (II) event1 - Power Button: device removed Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (**) Option "fd" "44" Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (II) event0 - Sleep Button: device removed Nov 24 18:50:10 diony kernel: [ 1221.728849] snd_hda_codec_hdmi hdaudioC1D0: HDMI: invalid ELD data byte 0 Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (II) systemd-logind: got pause for 13:65 Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (II) systemd-logind: got pause for 13:64 Nov 24 18:50:10 diony /usr/lib/gdm3/gdm-x-session[1242]: (II) systemd-logind: got pause for 13:66
此外，还考虑这个：https://ubuntuhandbook.org/index.php/2020/05/lid-close-behavior-ubuntu-20-04/
主要是编辑 /etc/systemd/logind.conf 这个文件。
这个文件原文是：
# This file is part of systemd. # # systemd is free software; you can redistribute it and/or modify it # under the terms of the GNU Lesser General Public License as published by # the Free Software Foundation; either version 2.1 of the License, or # (at your option) any later version. # # Entries in this file show the compile time defaults. # You can change settings by editing this file. # Defaults can be restored by simply deleting this file. # # See logind.conf(5) for details. [Login] #NAutoVTs=6 #ReserveVT=6 #KillUserProcesses=no #KillOnlyUsers= #KillExcludeUsers=root #InhibitDelayMaxSec=5 #HandlePowerKey=poweroff #HandleSuspendKey=suspend #HandleHibernateKey=hibernate #HandleLidSwitch=suspend #HandleLidSwitchExternalPower=suspend #HandleLidSwitchDocked=ignore #PowerKeyIgnoreInhibited=no #SuspendKeyIgnoreInhibited=no #HibernateKeyIgnoreInhibited=no #LidSwitchIgnoreInhibited=yes #HoldoffTimeoutSec=30s #IdleAction=ignore #IdleActionSec=30min #RuntimeDirectorySize=10% #RemoveIPC=yes #InhibitorsMax=8192 #SessionsMax=8192
对 #HandleLidSwitch=suspend 一行修改行为：
- HandleLidSwitch=lock – 合盖即锁定
- HandleLidSwitch=ignore – 合盖即什么都不做
- HandleLidSwitch=poweroff – 合盖即关机
- HandleLidSwitch=hibernate – 合盖即进入 hibernate 待机状态
当然出于时间考虑直接 mask 掉这几个行为，对目前我的机器而言应该都一样（任何时候都不关机，除非主动手动关）
