Hi,

I am working with SLES12 and KDE and have some problem with its performance. After some time of using my servers desktop starts freezing for some time. This 'hanging' state holds for a few seconds where you can not interact at all. It is possible to move the cursor but thre is no reaction to any clicking action. After a few seconds you can continue working (sometimes it takes a few minutes). To find out more about this behaviour I did some monitoring and testing.

I found out that the hanging session doesnt affect any other running session. So I was able to create the hanging state while monitoring the system. During the hanging state there is no process that has a big CPU or RAM utilization. The only noticable parameter is the I/O utilization which is a bit higher than normal. The slightly higher I/O utilization was raised by the usage of a virtual machine or by copying big files. My suggestion is that it has something to do with I/O but I was not able to find any appropriate solution. I tried different I/O Schedulers and I used different kernels (default and desktop) but it didnt help at all.

Does anyone have similar problems while using SLES 12? Or anyone have an idea what can cause these behaviour?

Information about my system:
HP DESK800 G1 (8 i7 cores and 16 GB RAM)
SLES 12
KDE 4.14.9
Kernel: 3.12.39-47.2-default/desktop

System messages during a hanging state:

Code:
2015-08-12T08:44:00.307225+02:00 sles12server polkitd[7487]: Unregistered Authentication Agent for unix-session:97 (system bus name :1.278, object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:44:00.459266+02:00 sles12server kdm: sles12server.network.com:2[7415]: pam_unix(xdm:session): session closed for user engin
2015-08-12T08:44:00.460891+02:00 sles12server org.kde.kuiserver[7832]: kuiserver: Fatal IO error: client killed
2015-08-12T08:44:00.519656+02:00 sles12server pulseaudio[14680]: [pulseaudio] main.c: User-configured server at {6cfa6ca0c1a94310810d5adc33ef07ab}unix:/run/user/1001/pulse/native, which appears to be local. Probing deeper.
2015-08-12T08:44:00.519820+02:00 sles12server pulseaudio[14681]: [pulseaudio] main.c: User-configured server at {6cfa6ca0c1a94310810d5adc33ef07ab}unix:/run/user/1001/pulse/native, which appears to be local. Probing deeper.
2015-08-12T08:44:00.528713+02:00 sles12server pulseaudio[14686]: [pulseaudio] main.c: User-configured server at {6cfa6ca0c1a94310810d5adc33ef07ab}unix:/run/user/1001/pulse/native, which appears to be local. Probing deeper.
2015-08-12T08:44:00.533803+02:00 sles12server pulseaudio[14685]: [pulseaudio] pid.c: Stale PID file, overwriting.
2015-08-12T08:44:00.604295+02:00 sles12server rtkit-daemon[7587]: Supervising 0 threads of 0 processes of 1 users.
2015-08-12T08:44:00.611035+02:00 sles12server rtkit-daemon[7587]: message repeated 4 times: [ Supervising 0 threads of 0 processes of 1 users.]
2015-08-12T08:44:00.645451+02:00 sles12server xinetd[3757]: EXIT: vnc2 status=0 duration=635(sec)
2015-08-12T08:44:00.649710+02:00 sles12server rtkit-daemon[7587]: Supervising 0 threads of 0 processes of 1 users.
2015-08-12T08:44:00.664712+02:00 sles12server rtkit-daemon[7587]: message repeated 9 times: [ Supervising 0 threads of 0 processes of 1 users.]
2015-08-12T08:44:00.686168+02:00 sles12server pulseaudio[14693]: [pulseaudio] pid.c: Daemon already running.
2015-08-12T08:44:00.700595+02:00 sles12server pulseaudio[14695]: [pulseaudio] pid.c: Daemon already running.
2015-08-12T08:44:01.811863+02:00 sles12server xinetd[3757]: START: vnc2 from=10.49.80.121
2015-08-12T08:44:01.842077+02:00 sles12server kdm_config[14753]: Multiple occurrences of section [General] in /usr/share/kde4/config/kdm/kdmrc. Consider merging them.
2015-08-12T08:44:01.842251+02:00 sles12server kdm_config[14753]: Multiple occurrences of section [X-*-Core] in /usr/share/kde4/config/kdm/kdmrc. Consider merging them.
2015-08-12T08:44:01.842343+02:00 sles12server kdm_config[14753]: Multiple occurrences of section [X-*-Greeter] in /usr/share/kde4/config/kdm/kdmrc. Consider merging them.
2015-08-12T08:44:01.842434+02:00 sles12server kdm_config[14753]: Multiple occurrences of key 'Language' in section [X-*-Greeter] of /usr/share/kde4/config/kdm/kdmrc
2015-08-12T08:44:01.842499+02:00 sles12server kdm_config[14753]: Multiple occurrences of section [X-:*-Core] in /usr/share/kde4/config/kdm/kdmrc. Consider merging them.
2015-08-12T08:44:01.842534+02:00 sles12server kdm_config[14753]: Multiple occurrences of section [X-:0-Core] in /usr/share/kde4/config/kdm/kdmrc. Consider merging them.
2015-08-12T08:44:01.842560+02:00 sles12server kdm_config[14753]: Multiple occurrences of key 'AutoLoginEnable' in section [X-:0-Core] of /usr/share/kde4/config/kdm/kdmrc
2015-08-12T08:44:01.842584+02:00 sles12server kdm_config[14753]: Invalid option value 'engin,runtime1,runtime2,' at /usr/share/kde4/config/kdm/kdmrc:43
2015-08-12T08:44:09.571402+02:00 sles12server kdm: sles12server.network.com:2[14758]: pam_unix(xdm:session): session opened for user engin by (uid=0)
2015-08-12T08:44:09.575093+02:00 sles12server kernel: [59366.384312] type=1006 audit(1439361849.567:99): pid=14758 uid=0 old auid=4294967295 new auid=1001 old ses=4294967295 new ses=98 res=1
2015-08-12T08:44:10.866481+02:00 sles12server dbus[2092]: [system] Activating via systemd: service name='org.freedesktop.Avahi' unit='dbus-org.freedesktop.Avahi.service'
2015-08-12T08:44:10.866650+02:00 sles12server dbus[2092]: [system] Activation via systemd failed for unit 'dbus-org.freedesktop.Avahi.service': Unit dbus-org.freedesktop.Avahi.service failed to load: No such file or directory.
2015-08-12T08:44:11.945588+02:00 sles12server pulseaudio[15202]: Daemon already running.
2015-08-12T08:44:11.969167+02:00 sles12server pulseaudio[15217]: Daemon already running.
2015-08-12T08:44:12.150906+02:00 sles12server polkitd[7487]: Registered Authentication Agent for unix-session:98 (system bus name :1.307 [/usr/lib64/kde4/libexec/polkit-kde-authentication-agent-1], object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:44:36.079627+02:00 sles12server kdm[6712]: Cannot execute 'grub': not in $PATH.
2015-08-12T08:44:38.432537+02:00 sles12server polkitd[7487]: Unregistered Authentication Agent for unix-session:98 (system bus name :1.307, object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:44:38.524018+02:00 sles12server kdm: sles12server.network.com:2[14758]: pam_unix(xdm:session): session closed for user engin
2015-08-12T08:44:38.525990+02:00 sles12server org.kde.kuiserver[14940]: kuiserver: Fatal IO error: client killed
2015-08-12T08:44:38.532635+02:00 sles12server xinetd[3757]: EXIT: vnc2 status=0 duration=37(sec)
2015-08-12T08:45:01.975452+02:00 sles12server cron[15823]: pam_unix(crond:session): session opened for user root by (uid=0)
2015-08-12T08:45:01.978896+02:00 sles12server systemd: pam_unix(systemd-user:session): session opened for user root by (uid=0)
2015-08-12T08:45:01.979089+02:00 sles12server kernel: [59418.811463] type=1006 audit(1439361901.974:100): pid=15823 uid=0 old auid=4294967295 new auid=0 old ses=4294967295 new ses=99 res=1
2015-08-12T08:45:02.003593+02:00 sles12server CRON[15823]: pam_unix(crond:session): session closed for user root
2015-08-12T08:45:02.011844+02:00 sles12server systemd: pam_unix(systemd-user:session): session closed for user root
2015-08-12T08:45:29.324782+02:00 sles12server polkit-agent-helper-1[6425]: pam_unix(polkit-1:auth): authentication failure; logname= uid=1001 euid=0 tty= ruser=root rhost=  user=root
2015-08-12T08:45:30.064534+02:00 sles12server polkitd[7487]: Operator of unix-session:1 FAILED to authenticate to gain authorization for action org.kde.powerdevil.backlighthelper.brightness for system-bus-name::1.20 [kdeinit4: kded4 [kdeinit]] (owned by unix-user:engin)
2015-08-12T08:45:38.483931+02:00 sles12server su: pam_unix(su-l:session): session closed for user root
2015-08-12T08:45:38.484773+02:00 sles12server su: pam_unix(su-l:session): session closed for user root
2015-08-12T08:45:41.653196+02:00 sles12server kdm[6712]: Cannot execute 'grub': not in $PATH.
2015-08-12T08:45:43.089497+02:00 sles12server polkitd[7487]: Unregistered Authentication Agent for unix-session:1 (system bus name :1.51, object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:45:43.238199+02:00 sles12server kdm: :0[6786]: pam_unix(xdm:session): session closed for user engin
2015-08-12T08:45:43.239411+02:00 sles12server org.kde.kuiserver[7076]: kuiserver: Fatal IO error: client killed
2015-08-12T08:45:43.630643+02:00 sles12server kdm[6712]: plymouth should quit after server startup
2015-08-12T08:45:43.737326+02:00 sles12server kdm[6712]: Quitting Plymouth with transition
2015-08-12T08:45:43.739098+02:00 sles12server kdm[6712]: Is Plymouth still running? no
2015-08-12T08:45:49.805521+02:00 sles12server kdm: :0[16400]: pam_unix(xdm:session): session opened for user engin by (uid=0)
2015-08-12T08:45:49.807088+02:00 sles12server kernel: [59466.662710] type=1006 audit(1439361949.801:101): pid=16400 uid=0 old auid=4294967295 new auid=1001 old ses=4294967295 new ses=100 res=1
2015-08-12T08:45:50.684198+02:00 sles12server dbus[2092]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
2015-08-12T08:45:50.694316+02:00 sles12server dbus[2092]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
2015-08-12T08:45:50.884569+02:00 sles12server dbus[2092]: [system] Activating via systemd: service name='org.freedesktop.Avahi' unit='dbus-org.freedesktop.Avahi.service'
2015-08-12T08:45:50.884744+02:00 sles12server dbus[2092]: [system] Activation via systemd failed for unit 'dbus-org.freedesktop.Avahi.service': Unit dbus-org.freedesktop.Avahi.service failed to load: No such file or directory.
2015-08-12T08:45:51.789625+02:00 sles12server pulseaudio[16795]: Daemon already running.
2015-08-12T08:45:51.817120+02:00 sles12server pulseaudio[16804]: Daemon already running.
2015-08-12T08:45:51.872413+02:00 sles12server pulseaudio[14685]: [pulseaudio] module.c: Module "module-device-manager" should be loaded once at most. Refusing to load.
2015-08-12T08:45:51.938634+02:00 sles12server polkitd[7487]: Registered Authentication Agent for unix-session:100 (system bus name :1.323 [/usr/lib64/kde4/libexec/polkit-kde-authentication-agent-1], object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:47:10.046677+02:00 sles12server kdm[6712]: Cannot execute 'grub': not in $PATH.
2015-08-12T08:47:11.873300+02:00 sles12server polkitd[7487]: Unregistered Authentication Agent for unix-session:100 (system bus name :1.323, object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:47:11.990168+02:00 sles12server kdm: :0[16400]: pam_unix(xdm:session): session closed for user engin
2015-08-12T08:47:11.991496+02:00 sles12server org.kde.kuiserver[16546]: kuiserver: Fatal IO error: client killed
2015-08-12T08:47:12.375519+02:00 sles12server kdm[6712]: plymouth should quit after server startup
2015-08-12T08:47:12.477523+02:00 sles12server kdm[6712]: Quitting Plymouth with transition
2015-08-12T08:47:12.479388+02:00 sles12server kdm[6712]: Is Plymouth still running? no
2015-08-12T08:47:21.676716+02:00 sles12server kdm: :0[17763]: pam_unix(xdm:session): session opened for user engin by (uid=0)
2015-08-12T08:47:21.679089+02:00 sles12server kernel: [59558.574473] type=1006 audit(1439362041.674:102): pid=17763 uid=0 old auid=4294967295 new auid=1001 old ses=4294967295 new ses=101 res=1
2015-08-12T08:47:22.564814+02:00 sles12server dbus[2092]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
2015-08-12T08:47:22.576266+02:00 sles12server dbus[2092]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
2015-08-12T08:47:22.790270+02:00 sles12server dbus[2092]: [system] Activating via systemd: service name='org.freedesktop.Avahi' unit='dbus-org.freedesktop.Avahi.service'
2015-08-12T08:47:22.790435+02:00 sles12server dbus[2092]: [system] Activation via systemd failed for unit 'dbus-org.freedesktop.Avahi.service': Unit dbus-org.freedesktop.Avahi.service failed to load: No such file or directory.
2015-08-12T08:47:23.675522+02:00 sles12server pulseaudio[18183]: Daemon already running.
2015-08-12T08:47:23.689259+02:00 sles12server pulseaudio[14685]: [pulseaudio] module.c: Module "module-device-manager" should be loaded once at most. Refusing to load.
2015-08-12T08:47:23.713211+02:00 sles12server pulseaudio[18197]: Daemon already running.
2015-08-12T08:47:23.848383+02:00 sles12server polkitd[7487]: Registered Authentication Agent for unix-session:101 (system bus name :1.338 [/usr/lib64/kde4/libexec/polkit-kde-authentication-agent-1], object path /org/kde/PolicyKit1/AuthenticationAgent, locale de_DE.UTF-8)
2015-08-12T08:48:13.920593+02:00 sles12server su: (to root) engin on pts/4
2015-08-12T08:48:13.920789+02:00 sles12server su: pam_unix(su-l:session): session opened for user root by engin(uid=1001)
2015-08-12T08:49:06.555592+02:00 sles12server su: pam_unix(su-l:auth): authentication failure; logname=engin uid=1001 euid=0 tty=pts/7 ruser=engin rhost=  user=root
2015-08-12T08:49:08.698758+02:00 sles12server su: FAILED SU (to root) engin on pts/7
2015-08-12T08:49:20.795738+02:00 sles12server su: (to root) engin on pts/7
2015-08-12T08:49:20.795891+02:00 sles12server su: pam_unix(su-l:session): session opened for user root by engin(uid=1001)
2015-08-12T08:50:44.088924+02:00 sles12server su: (to root) engin on pts/6
2015-08-12T08:50:44.089086+02:00 sles12server su: pam_unix(su-l:session): session opened for user root by engin(uid=1001)