我的设置是在 Dell Precision 380 上，配备 4GB RAM、Intel® Pentium(R) 4 CPU 3.00GHz × 2、NVA8 上的 Gallium 0.4。Ubuntu 16.04 位于 67GB 分区中，另一个分区有 Win XP，但这已经很长时间没有用了。硬盘已通过测试，没有问题。
症状是，在过去几周里，大约 50% 的系统启动让我进入登录页面，但无法进入桌面。有时重新启动有效，其他时候我不得不求助于通用模式或甚至恢复模式。我在成功重新启动后复制了以下系统日志输出，其中显示了几个奇怪的事情，这可能解释了为什么系统加载速度比以前慢：
Dec 15 09:35:02 henry-Precision-WorkStation-380 CRON[4163]: pam_unix(cron:session): session closed for user root
Dec 15 09:44:09 henry-Precision-WorkStation-380 polkitd(authority=local): Unregistered Authentication Agent for unix-session:c2 (system bus name :1.79, object path /org/gnome/PolicyKit1/AuthenticationAgent, locale en_GB.UTF-8) (disconnected from bus)
Dec 15 09:44:12 henry-Precision-WorkStation-380 systemd-logind[900]: System is rebooting.
Dec 15 09:45:08 henry-Precision-WorkStation-380 systemd-logind[903]: New seat seat0.
Dec 15 09:45:08 henry-Precision-WorkStation-380 systemd-logind[903]: Watching system buttons on /dev/input/event1 (Power Button)
Dec 15 09:45:08 henry-Precision-WorkStation-380 systemd-logind[903]: Watching system buttons on /dev/input/event0 (Power Button)
Dec 15 09:45:25 henry-Precision-WorkStation-380 lightdm: PAM unable to dlopen(pam_kwallet.so): /lib/security/pam_kwallet.so: cannot open shared object file: No such file or directory
Dec 15 09:45:25 henry-Precision-WorkStation-380 lightdm: PAM adding faulty module: pam_kwallet.so
Dec 15 09:45:25 henry-Precision-WorkStation-380 lightdm: PAM unable to dlopen(pam_kwallet5.so): /lib/security/pam_kwallet5.so: cannot open shared object file: No such file or directory
Dec 15 09:45:25 henry-Precision-WorkStation-380 lightdm: PAM adding faulty module: pam_kwallet5.so
Dec 15 09:45:26 henry-Precision-WorkStation-380 lightdm: pam_unix(lightdm-greeter:session): session opened for user lightdm by (uid=0)
Dec 15 09:45:26 henry-Precision-WorkStation-380 systemd-logind[903]: New session c1 of user lightdm.
Dec 15 09:45:26 henry-Precision-WorkStation-380 systemd: pam_unix(systemd-user:session): session opened for user lightdm by (uid=0)
Dec 15 09:45:39 henry-Precision-WorkStation-380 lightdm: PAM unable to dlopen(pam_kwallet.so): /lib/security/pam_kwallet.so: cannot open shared object file: No such file or directory
Dec 15 09:45:39 henry-Precision-WorkStation-380 lightdm: PAM adding faulty module: pam_kwallet.so
Dec 15 09:45:39 henry-Precision-WorkStation-380 lightdm: PAM unable to dlopen(pam_kwallet5.so): /lib/security/pam_kwallet5.so: cannot open shared object file: No such file or directory
Dec 15 09:45:39 henry-Precision-WorkStation-380 lightdm: PAM adding faulty module: pam_kwallet5.so
Dec 15 09:45:39 henry-Precision-WorkStation-380 lightdm: pam_succeed_if(lightdm:auth): requirement "user ingroup nopasswdlogin" not met by user "henry"
Dec 15 09:45:58 henry-Precision-WorkStation-380 lightdm: pam_unix(lightdm-greeter:session): session closed for user lightdm
Dec 15 09:45:59 henry-Precision-WorkStation-380 lightdm: pam_unix(lightdm:session): session opened for user henry by (uid=0)
Dec 15 09:45:59 henry-Precision-WorkStation-380 systemd: pam_unix(systemd-user:session): session opened for user henry by (uid=0)
Dec 15 09:45:59 henry-Precision-WorkStation-380 systemd-logind[903]: New session c2 of user henry.
Dec 15 09:46:06 henry-Precision-WorkStation-380 dbus[960]: [system] Failed to activate service 'org.bluez': timed out
Dec 15 09:46:10 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: The SSH agent was already initialized
Dec 15 09:46:10 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: The Secret Service was already initialized
Dec 15 09:46:11 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: The PKCS#11 component was already initialized
Dec 15 09:46:12 henry-Precision-WorkStation-380 polkitd(authority=local): Registered Authentication Agent for unix-session:c2 (system bus name :1.82 [/usr/lib/policykit-1-gnome/polkit-gnome-authentication-agent-1], object path /org/gnome/PolicyKit1/AuthenticationAgent, locale en_GB.UTF-8)
Dec 15 09:46:24 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: couldn't allocate secure memory to keep passwords and or keys from being written to the disk
Dec 15 09:46:25 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/10, but it's already registered
Dec 15 09:46:26 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/4, but it's already registered
Dec 15 09:46:27 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/6, but it's already registered
Dec 15 09:46:28 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/2, but it's already registered
Dec 15 09:46:30 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/14, but it's already registered
Dec 15 09:46:31 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/8, but it's already registered
Dec 15 09:46:32 henry-Precision-WorkStation-380 dbus[960]: [system] Failed to activate service 'org.bluez': timed out
Dec 15 09:46:36 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/4, but it's already registered
Dec 15 09:46:37 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/14, but it's already registered
Dec 15 09:46:39 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/2, but it's already registered
Dec 15 09:46:39 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/10, but it's already registered
Dec 15 09:46:40 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/6, but it's already registered
Dec 15 09:46:41 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/8, but it's already registered
Dec 15 09:46:43 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/2, but it's already registered
Dec 15 09:46:44 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/6, but it's already registered
Dec 15 09:46:44 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/14, but it's already registered
Dec 15 09:46:44 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/4, but it's already registered
Dec 15 09:46:45 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/10, but it's already registered
Dec 15 09:46:45 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/8, but it's already registered
Dec 15 09:46:46 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/2, but it's already registered
Dec 15 09:46:46 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/6, but it's already registered
Dec 15 09:46:47 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/14, but it's already registered
Dec 15 09:46:47 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/4, but it's already registered
Dec 15 09:46:48 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/10, but it's already registered
Dec 15 09:46:48 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/8, but it's already registered
Dec 15 09:46:48 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/2, but it's already registered
Dec 15 09:46:49 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/6, but it's already registered
Dec 15 09:46:49 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/14, but it's already registered
Dec 15 09:46:49 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/4, but it's already registered
Dec 15 09:46:50 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/10, but it's already registered
Dec 15 09:46:50 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/8, but it's already registered
Dec 15 09:46:51 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/2, but it's already registered
Dec 15 09:46:51 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/6, but it's already registered
Dec 15 09:46:51 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/14, but it's already registered
Dec 15 09:46:52 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/4, but it's already registered
Dec 15 09:46:52 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/10, but it's already registered
Dec 15 09:46:52 henry-Precision-WorkStation-380 gnome-keyring-daemon[1746]: asked to register item /org/freedesktop/secrets/collection/login/8, but it's already registered
Dec 15 09:46:59 henry-Precision-WorkStation-380 polkitd(authority=local): Operator of unix-session:c2 successfully authenticated as unix-user:henry to gain ONE-SHOT authorization for action com.ubuntu.apport.apport-gtk-root for unix-process:1751:7601 [/sbin/upstart --user] (owned by unix-user:henry)
Dec 15 09:46:59 henry-Precision-WorkStation-380 pkexec: pam_unix(polkit-1:session): session opened for user root by (uid=1000)
Dec 15 09:46:59 henry-Precision-WorkStation-380 pkexec: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
Dec 15 09:46:59 henry-Precision-WorkStation-380 pkexec[2660]: henry: Executing command [USER=root] [TTY=unknown] [CWD=/home/henry] [COMMAND=/usr/share/apport/apport-gtk]
Dec 15 09:47:21 henry-Precision-WorkStation-380 pkexec: pam_unix(polkit-1:session): session opened for user root by (uid=1000)
Dec 15 09:47:21 henry-Precision-WorkStation-380 pkexec: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
Dec 15 09:47:21 henry-Precision-WorkStation-380 pkexec[2986]: henry: Executing command [USER=root] [TTY=unknown] [CWD=/home/henry] [COMMAND=/usr/lib/update-notifier/package-system-locked]
Dec 15 09:47:29 henry-Precision-WorkStation-380 systemd-logind[903]: Removed session c1.
如能得到有关如何防止启动失败的任何建议，我们将不胜感激。
亨利