最近 sddm 在 Arch Linux 上显示登录屏幕变得非常慢。在我看到启动消息“已达到图形用户界面目标”（或类似消息）后，在显示 sddm 问候语之前有超过 10 秒的长时间延迟。
下面的日志显示整个启动过程很慢：
Startup finished in 17.085s (firmware) + 4.763s (loader) + 6.253s (kernel) + 15.786s (userspace) = 43.890s.
然而，从“启动简单桌面显示管理器”（5月15日17:53:36）到“Greeter会话成功启动”（5月15日17:53:59）是13秒。延迟的大幅增加似乎与用户.face.icon文件的显示有关，尽管这只是猜测。
希望有人能在下面的日志消息中看到一些线索。
May 15 17:54:01 desktop1 sddm-greeter[660]: Message received from daemon: HostName
May 15 17:54:01 desktop1 sddm-greeter[660]: Message received from daemon: Capabilities
May 15 17:54:01 desktop1 sddm-greeter[660]: QDBusConnection: name 'org.freedesktop.UDisks2' had owner '' but we thought it was ':1.54'
May 15 17:54:01 desktop1 sddm-greeter[660]: Adding view for "HDMI-2" QRect(0,0 2560x1440)
May 15 17:54:01 desktop1 sddm-greeter[660]: file:///usr/share/sddm/themes/breeze/components/VirtualKeyboard.qml:20:1: module "QtQuick.VirtualKeyboard" is not installed
May 15 17:54:01 desktop1 sddm-greeter[660]: inotify_add_watch("/etc/fstab") failed: "Permission denied"
May 15 17:54:01 desktop1 systemd[1]: Started Daemon for power management.
May 15 17:54:01 desktop1 dbus-daemon[410]: [system] Successfully activated service 'org.freedesktop.UPower'
May 15 17:54:00 desktop1 udisksd[666]: Acquired the name org.freedesktop.UDisks2 on the system message bus
May 15 17:54:00 desktop1 systemd[1]: Starting Daemon for power management...
May 15 17:54:00 desktop1 dbus-daemon[410]: [system] Activating via systemd: service name='org.freedesktop.UPower' unit='upower.service' requested by ':1.53' (uid=995 pid=660 comm="/usr/b>
May 15 17:54:00 desktop1 systemd[1]: Started Disk Manager.
May 15 17:54:00 desktop1 dbus-daemon[410]: [system] Successfully activated service 'org.freedesktop.UDisks2'
May 15 17:54:00 desktop1 udisksd[666]: udisks daemon version 2.7.6 starting
May 15 17:54:00 desktop1 systemd[1]: Starting Disk Manager...
May 15 17:54:00 desktop1 dbus-daemon[410]: [system] Activating via systemd: service name='org.freedesktop.UDisks2' unit='udisks2.service' requested by ':1.53' (uid=995 pid=660 comm="/usr>
May 15 17:54:00 desktop1 sddm-greeter[660]: Cannot watch QRC-like path ":/icons/hicolor/index.theme"
May 15 17:54:00 desktop1 sddm-greeter[660]: QObject::installEventFilter(): Cannot filter events for objects in a different thread.
May 15 17:54:00 desktop1 sddm-greeter[660]: QObject: Cannot create children for a parent that is in a different thread.
(Parent is SDDM::GreeterApp(0x7fff5551e800), parent's thread is QThread(0x55fe866984a0), current thread is QThread(0x55fe866f9ae0)
May 15 17:53:59 desktop1 systemd[654]: Started D-Bus User Message Bus.
May 15 17:53:59 desktop1 sddm-greeter[660]: QObject: Cannot create children for a parent that is in a different thread.
(Parent is SDDM::GreeterApp(0x7fff5551e800), parent's thread is QThread(0x55fe866984a0), current thread is QThread(0x55fe866f9ae0)
May 15 17:53:59 desktop1 sddm-greeter[660]: QObject::installEventFilter(): Cannot filter events for objects in a different thread.
May 15 17:53:59 desktop1 sddm-greeter[660]: QObject: Cannot create children for a parent that is in a different thread.
(Parent is SDDM::GreeterApp(0x7fff5551e800), parent's thread is QThread(0x55fe866984a0), current thread is QThread(0x55fe866f9ae0)
May 15 17:53:59 desktop1 sddm-greeter[660]: QObject: Cannot create children for a parent that is in a different thread.
(Parent is SDDM::GreeterApp(0x7fff5551e800), parent's thread is QThread(0x55fe866984a0), current thread is QThread(0x55fe866f9ae0)
May 15 17:53:59 desktop1 sddm-greeter[660]: QObject: Cannot create children for a parent that is in a different thread.
(Parent is SDDM::GreeterApp(0x7fff5551e800), parent's thread is QThread(0x55fe866984a0), current thread is QThread(0x55fe866f9ae0)
May 15 17:53:59 desktop1 sddm-greeter[660]: QObject: Cannot create children for a parent that is in a different thread.
(Parent is SDDM::GreeterApp(0x7fff5551e800), parent's thread is QThread(0x55fe866984a0), current thread is QThread(0x55fe866f9ae0)
May 15 17:53:59 desktop1 sddm-greeter[660]: Loading file:///usr/share/sddm/themes/breeze/Main.qml...
May 15 17:53:59 desktop1 sddm[630]: Message received from greeter: Connect
May 15 17:53:59 desktop1 sddm-greeter[660]: Connected to the daemon.
May 15 17:53:59 desktop1 sddm-greeter[660]: inotify_add_watch("/usr/share/wayland-sessions") failed: "No such file or directory"
May 15 17:53:59 desktop1 sddm-greeter[660]: Reading from "/usr/share/xsessions/plasma.desktop"
May 15 17:53:59 desktop1 sddm-greeter[660]: Loading theme configuration from "/usr/share/sddm/themes/breeze/theme.conf"
May 15 17:53:59 desktop1 sddm-greeter[660]: High-DPI autoscaling not Enabled
May 15 17:53:59 desktop1 sddm[630]: Greeter session started successfully
May 15 17:53:59 desktop1 systemd[1]: Started User Manager for UID 995.
May 15 17:53:59 desktop1 systemd[654]: Startup finished in 82ms.
May 15 17:53:59 desktop1 systemd[654]: Reached target Default.
May 15 17:53:59 desktop1 systemd[654]: Reached target Basic System.
May 15 17:53:59 desktop1 systemd[654]: Reached target Sockets.
May 15 17:53:59 desktop1 systemd[654]: Listening on D-Bus User Message Bus Socket.
May 15 17:53:59 desktop1 systemd[654]: Reached target Paths.
May 15 17:53:59 desktop1 systemd[654]: Listening on GnuPG cryptographic agent and passphrase cache (restricted).
May 15 17:53:59 desktop1 systemd[654]: Listening on GnuPG cryptographic agent (ssh-agent emulation).
May 15 17:53:59 desktop1 systemd[654]: Listening on GnuPG network certificate management daemon.
May 15 17:53:59 desktop1 systemd[654]: Listening on GnuPG cryptographic agent and passphrase cache (access for web browsers).
May 15 17:53:59 desktop1 systemd[654]: Listening on GnuPG cryptographic agent and passphrase cache.
May 15 17:53:59 desktop1 systemd[654]: Listening on Sound System.
May 15 17:53:59 desktop1 systemd[654]: Reached target Timers.
May 15 17:53:59 desktop1 systemd[654]: Starting D-Bus User Message Bus Socket.
May 15 17:53:58 desktop1 systemd[654]: pam_unix(systemd-user:session): session opened for user sddm by (uid=0)
May 15 17:53:58 desktop1 systemd[1]: Started Session c1 of user sddm.
May 15 17:53:58 desktop1 systemd-logind[409]: New session c1 of user sddm.
May 15 17:53:58 desktop1 systemd[1]: Starting User Manager for UID 995...
May 15 17:53:58 desktop1 systemd[1]: Created slice User Slice of sddm.
May 15 17:53:58 desktop1 sddm-helper[652]: pam_unix(sddm-greeter:session): session opened for user sddm by (uid=0)
May 15 17:53:58 desktop1 sddm-helper[652]: [PAM] returning.
May 15 17:53:58 desktop1 sddm-helper[652]: [PAM] Authenticating...
May 15 17:53:58 desktop1 sddm-helper[652]: [PAM] Starting...
May 15 17:53:58 desktop1 sddm[630]: Adding cookie to "/var/run/sddm/{d4e3bc53-809f-3ca5-a1e-b1d287e870b1}"
May 15 17:53:58 desktop1 sddm[630]: Greeter starting...
May 15 17:53:58 desktop1 sddm[630]: Loading theme configuration from "/usr/share/sddm/themes/breeze/theme.conf"
May 15 17:53:58 desktop1 sddm[630]: Socket server started.
May 15 17:53:58 desktop1 sddm[630]: Socket server starting...
May 15 17:53:58 desktop1 sddm[630]: Display server started.
May 15 17:53:58 desktop1 sddm[630]: Running display setup script "/usr/share/sddm/scripts/Xsetup"
May 15 17:53:58 desktop1 sddm[630]: Setting default cursor
May 15 17:53:57 desktop1 sddm[630]: Running: /usr/bin/X -nolisten tcp -auth /var/run/sddm/{d4e3bc53-809f-3ca5-a1e-b1d287e870b1} -background none -noreset -displayfd 17 -seat seat0 vt1
May 15 17:53:57 desktop1 sddm[630]: Display server starting...
May 15 17:53:57 desktop1 sddm[630]: Loading theme configuration from ""
May 15 17:53:57 desktop1 sddm[630]: Adding new display on vt 1 ...
May 15 17:53:57 desktop1 sddm[630]: Starting...
May 15 17:53:57 desktop1 sddm[630]: Logind interface found
May 15 17:53:57 desktop1 sddm[630]: Initializing...
May 15 17:53:57 desktop1 kernel: random: 6 urandom warning(s) missed due to ratelimiting
May 15 17:53:57 desktop1 kernel: random: crng init done
May 15 17:53:42 desktop1 dhcpcd[507]: eth0: no IPv6 Routers available
May 15 17:53:37 desktop1 systemd[1]: Startup finished in 17.085s (firmware) + 4.763s (loader) + 6.253s (kernel) + 15.786s (userspace) = 43.890s.
May 15 17:53:37 desktop1 systemd[1]: Reached target Graphical Interface.
May 15 17:53:37 desktop1 systemd[1]: Reached target Multi-User System.
May 15 17:53:37 desktop1 systemd[1]: Started Make remote CUPS printers available locally.
May 15 17:53:37 desktop1 systemd[1]: Started CUPS Scheduler.
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 systemd[1]: Started Simple Desktop Display Manager.
May 15 17:53:36 desktop1 systemd[1]: Started Permit User Sessions.
May 15 17:53:36 desktop1 systemd[1]: Starting Permit User Sessions...
May 15 17:53:36 desktop1 systemd[1]: Reached target Remote File Systems.
May 15 17:53:36 desktop1 systemd[1]: Started Manage, Install and Generate Color Profiles.
May 15 17:53:36 desktop1 systemd[1]: Mounted /home/usercommon/Finance/Syncd.
May 15 17:53:36 desktop1 systemd[1]: Mounted /var/cache/pacman.
May 15 17:53:36 desktop1 systemd[1]: Mounted /kit.
May 15 17:53:36 desktop1 systemd[1]: Mounted /home/mari/fileserver/Desktop.
May 15 17:53:36 desktop1 systemd[1]: Mounted /home/usercommon/Finance/Receipts.
May 15 17:53:36 desktop1 systemd[1]: Mounted /home/jessica/Documents.
May 15 17:53:36 desktop1 systemd[1]: Mounted /backup/admins.
May 15 17:53:36 desktop1 systemd[1]: Mounted /home/natasha/Documents.
May 15 17:53:36 desktop1 systemd[1]: Mounted /backup/files.
May 15 17:53:36 desktop1 systemd[1]: Mounted /home/usercommon/Ventures.
May 15 17:53:58 desktop1 sddm[630]: Setting default cursor
May 15 17:53:57 desktop1 sddm[630]: Running: /usr/bin/X -nolisten tcp -auth /var/run/sddm/{d4e3bc53-809f-3ca5-a1e-b1d287e870b1} -background none -noreset -displayfd 17 -seat seat0 vt1
May 15 17:53:57 desktop1 sddm[630]: Display server starting...
May 15 17:53:57 desktop1 sddm[630]: Loading theme configuration from ""
May 15 17:53:57 desktop1 sddm[630]: Adding new display on vt 1 ...
May 15 17:53:57 desktop1 sddm[630]: Starting...
May 15 17:53:57 desktop1 sddm[630]: Logind interface found
May 15 17:53:57 desktop1 sddm[630]: Initializing...
May 15 17:53:57 desktop1 kernel: random: 6 urandom warning(s) missed due to ratelimiting
May 15 17:53:57 desktop1 kernel: random: crng init done
May 15 17:53:42 desktop1 dhcpcd[507]: eth0: no IPv6 Routers available
May 15 17:53:37 desktop1 systemd[1]: Startup finished in 17.085s (firmware) + 4.763s (loader) + 6.253s (kernel) + 15.786s (userspace) = 43.890s.
May 15 17:53:37 desktop1 systemd[1]: Reached target Graphical Interface.
May 15 17:53:37 desktop1 systemd[1]: Reached target Multi-User System.
May 15 17:53:37 desktop1 systemd[1]: Started Make remote CUPS printers available locally.
May 15 17:53:37 desktop1 systemd[1]: Started CUPS Scheduler.
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 colord[615]: failed to get session [pid 562]: No data available
May 15 17:53:36 desktop1 systemd[1]: Started Simple Desktop Display Manager.
我在多台计算机上看到同样的问题。全部运行带有plasmashell 5.12.5或更高版本的Arch Linux KDE。 Linux 4.16.8-1-ARCH #1 SMP PREEMPT 5 月 9 日星期三 11:25:02 UTC 2018 x86_64 GNU/Linux。
答案1
Haller 在 Arch Linux BBS 上写道：
It's a kernel problem:
https://bbs.archlinux.org/viewtopic.php?id=236696
这为我解决了这个问题：
pacman -Syu haveged
systemctl enable haveged.service
systemctl start haveged.service
这一更改将启动阶段的时间从 13 秒减少到约 1 秒：
我在两台不同的计算机上对此进行了测试，并在两台计算机上都得到了非常积极的结果。在内核问题得到解决之前，这对我来说将是一个令人满意的解决方法。