On Friday 02 January 2015, dep wrote:
> said Michele Calgaro:
> | On 12/28/2014 08:15 AM, dep wrote:
> | > sorry to be such a bother, but as long as i'm bringing things up,
> | > here's one that has been an issue for a couple of years and survived
> | > into R14.
> | >
> | > my desktop crashes, but in such a way as to not even be noticeable at
> | > first.
> | >
> | > i have in lieu of wallpaper xplanet set up as a realtime moon phase
> | > indicator, updating hourly. the way i tell the desktop has crashed is
> | > that it doesn't update -- in this case it last refreshed at 10:30 a.m.
> | > yesterday. i believe that i was probably editing pictures at that
> | > time, though would not swear to it.
> | >
> | > after it crashes, a right click on the desktop does not produce the
> | > expected menu. as it happens, kicker and everything else continues to
> | > function as expected -- in fact, it was just now that i noticed that
> | > the desktop itself had gone south.
> | >
> | > i thought i'd look in the x error log, bit i see that the one i have,
> | > ~/.xsession-errors, is of an unspecified file type and won't open in a
> | > text editor (it reports its size as 500.0 k).
> | >
> | > any idea if there's a log that might let me see what's going on here
> | > and if so what log it might be? bonus points, how i might restart the
> | > desktop without logging out and back in? extra bonus points, how i
> | > might fix it so it doesn't do this anymore? i'm running some flavor of
> | > ubuntu 12.04LTS -- i say some flavor because when i sought to upgrade
> | > a few days ago the ubuntu upgrader refused, citing third-party apps or
> | > a beta version of the opsys, or something; it didn't specify. i
> | > thought i had bog standard 12.04LTS on the machine but am apparently
> | > wrong.
> |
> |
> | sorry for the late reply. The desktop behavior is controlled by the
> | kdesktop process. When your desktop stops updating, from CLI type:
> | ps aux | grep desktop
> | and see if there is something like:
> | username      8414  0.4  0.7 260192 28956 pts/8    Sl   12:50   0:00
> | kdesktop
> 
> avahi     1973  0.0  0.0  32308  1732 ?        S     2014   0:01 
> avahi-daemon: running [dep-desktop.local]
> dep       3200  0.0  0.1 252184 17972 ?        Sl    2014   
> 1:04 /opt/trinity/bin/kdesktop
> dep      11289  0.0  0.0      0     0 ?        Z     2014   0:02 
> [kdesktop_lock] <defunct>
> dep      29758  0.0  0.0   9388   904 pts/0    S+   16:12   0:00 grep 
> desktop
> 
> nevertheless, it hasn't updated since 10:19:53 AM 26 December. and a rmb 
> click on the desktop does not produce the expected menu.
> 
> | If not, kdesktop has crashed. You can type:
> | kdesktop & from CLI to restart it (or alternatively Alt-F2 and then
> | kdesktop).
> 
> dep@dep-desktop:~$ kdesktop is already running!
> 
> | If this brings everything back in order, please let us know because we
> | need some more advanced testing to understand why and where kdesktop
> | crashed.
> 
> fwiw, top reports 3 zombies.

have you tried to kill the running kdesktop beforehand (not the defuncts)?
I assume it runns under process number 3200. Thus:
$ kill -9 3200

and than launch kdesktop again?

Gerhard
PS: "killall kdesktop" might work as well; be sure to have a konsole open for it.