[mythtv-users] after update frontend hangs burning 100% of CPU

[Paul Harrison]

On 01/04/13 05:11, D. Hugh Redelmeier wrote:
> [This might or might not be related to "update failed now fe crashes".]
>
> I updated a mythbuntu system from MythTV 0.25 to 0.26.  The Ubuntu is
> 12.04 LTS.
>
> I've never done a MythTV update before, only a very few reinstalls.
>
> Procedure:
>
> 0) backup the myth database
>
> 1) apply all updates that the Ubuntu wished to do
>
> 2) used the Mythbuntu Control Center: Repositories screen to change the
>     repositories from 0.25 to 0.26
>
> 3) apt-get update
>
> 4) apt-get upgrade
> 	This was only willing to upgrade 7 packages, leaving 7 behind
> 	so I told it to not go ahead
>
> 5) apt-get dist-upgrade
> 	This worked (or at least didn't produce diagnostics).
> 	But the mythtv-backend crashed in the process.
>
> 6) reboot (to get everything back to a sane state)
>
> 7) the backend seemed to hang.  After a few minutes I rebooted.
>     Now I know that the backend wasn't hung, it was just changing the
>     databse to the new schema.  After the reboot, it seemed to
>     continue from where it left off.
>
> 8) I started the frontend (normally I don't run it on this machine).
>     It seemed to hang.  The display was completely blank.
>
>     The backend was actually doing a database backup (why is
>     that the frontend's job?).
>
>     After finishing the backup, the frontend hung, with no display,
>     using 100% of one CPU core.
>
>     After waiting quite a few minutes, I used GDB to find out what
>     /usr/bin/mythfrontend.real was doing:
>
> #0  0x00007fd6ea21edd4 in _nv012tls () from /usr/lib/nvidia-current-updates/tls/libnvidia-tls.so.304.64
> #1  0x00007fd6f08df243 in ?? () from /usr/lib/nvidia-current-updates/libGL.so.1
> #2  0x00007fd6f08bc76a in ?? () from /usr/lib/nvidia-current-updates/libGL.so.1
> #3  0x00007fd6f9e7c92d in _dl_fini () at dl-fini.c:259
> #4  0x00007fd6f5675901 in __run_exit_handlers (status=1, listp=0x7fd6f59f2688, run_list_atexit=true) at exit.c:78
> #5  0x00007fd6f5675985 in __GI_exit (status=<optimized out>) at exit.c:100
> #6  0x00007fd6ebaead5a in _IceDefaultIOErrorHandler (iceConn=<optimized out>) at ../../src/error.c:602
> #7  0x00007fd6ebaf1cc4 in IceFlush (iceConn=0x1f91d80) at ../../src/misc.c:78
> #8  0x00007fd6f6963111 in sm_setProperty (vals=<optimized out>, num_vals=<optimized out>, type=<optimized out>, name=<optimized out>) at kernel/qapplication_x11.cpp:6003
> #9  sm_setProperty (name=<optimized out>, type=<optimized out>, num_vals=<optimized out>, vals=<optimized out>) at kernel/qapplication_x11.cpp:5991
> #10 0x00007fd6f6963d19 in sm_setProperty (name=..., value=...) at kernel/qapplication_x11.cpp:6018
> #11 0x00007fd6f6979e4b in sm_performSaveYourself (smd=0x1f90980) at kernel/qapplication_x11.cpp:6082
> #12 0x00007fd6f697a989 in sm_saveYourselfCallback (smcConn=<optimized out>, clientData=<optimized out>, saveType=<optimized out>, shutdown=<optimized out>, interactStyle=<optimized out>)
>      at kernel/qapplication_x11.cpp:6061
> #13 0x00007fd6ebd03dff in _SmcProcessMessage () from /usr/lib/x86_64-linux-gnu/libSM.so.6
> #14 0x00007fd6ebaf5fd6 in IceProcessMessages (iceConn=0x1f91d80, replyWait=0x0, replyReadyRet=0x0) at ../../src/process.c:341
> #15 0x00007fd6f609e281 in QMetaObject::activate (sender=0x1f90790, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fff8d6c6570) at kernel/qobject.cpp:3547
> #16 0x00007fd6f60eb2fe in QSocketNotifier::activated (this=<optimized out>, _t1=11) at .moc/release-shared/moc_qsocketnotifier.cpp:103
> #17 0x00007fd6f60a760b in QSocketNotifier::event (this=0x1f90790, e=0x7fff8d6c6b90) at kernel/qsocketnotifier.cpp:317
> #18 0x00007fd6f68f8894 in notify_helper (e=0x7fff8d6c6b90, receiver=0x1f90790, this=0x1de0cf0) at kernel/qapplication.cpp:4559
> #19 QApplicationPrivate::notify_helper (this=0x1de0cf0, receiver=0x1f90790, e=0x7fff8d6c6b90) at kernel/qapplication.cpp:4531
> #20 0x00007fd6f68fd713 in QApplication::notify (this=0x1de08b0, receiver=0x1f90790, e=0x7fff8d6c6b90) at kernel/qapplication.cpp:4420
> #21 0x00007fd6f6089e9c in QCoreApplication::notifyInternal (this=0x1de08b0, receiver=0x1f90790, event=0x7fff8d6c6b90) at kernel/qcoreapplication.cpp:876
> #22 0x00007fd6f60b8a97 in sendEvent (event=0x7fff8d6c6b90, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
> #23 socketNotifierSourceDispatch (source=0x1de3cb0) at kernel/qeventdispatcher_glib.cpp:110
> #24 0x00007fd6ec3c5d53 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
> #25 0x00007fd6ec3c60a0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
> #26 0x00007fd6ec3c6164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
> #27 0x00007fd6f60b93bf in QEventDispatcherGlib::processEvents (this=0x1de1fb0, flags=...) at kernel/qeventdispatcher_glib.cpp:424
> #28 0x00007fd6f69a0d5e in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
> #29 0x00007fd6f6088c82 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
> #30 0x00007fd6f6088ed7 in QEventLoop::exec (this=0x7fff8d6c6dc0, flags=...) at kernel/qeventloop.cpp:204
> #31 0x00007fd6f82ac8eb in MythDialog::exec (this=0x22c2af0) at mythdialogs.cpp:181
> #32 0x00007fd6f82d1d1a in SchemaUpgradeWizard::GuiPrompt (this=<optimized out>, message=..., upgradable=true, expert=false) at schemawizard.cpp:161
> #33 0x00007fd6f82d263e in SchemaUpgradeWizard::PromptForUpgrade (this=0x20414f0, name=0x7fd68cc1ffef "Music", upgradeAllowed=<optimized out>, upgradeIfNoUI=false, minDBMSmajor=<optimized out>,
>      minDBMSminor=0, minDBMSpoint=0) at schemawizard.cpp:377
> #34 0x00007fd68cb2533c in UpgradeMusicDatabaseSchema () at dbcheck.cpp:113
> #35 0x00007fd68cafd659 in mythplugin_init (libversion=<optimized out>) at main.cpp:664
> #36 0x00007fd6f82bd2d5 in init (this=0x2294f30, libversion=<optimized out>) at mythplugin.cpp:42
> #37 MythPluginManager::init_plugin (this=0x205d1e0, plugname=...) at mythplugin.cpp:184
> #38 0x00007fd6f82bf637 in MythPluginManager::MythPluginManager (this=0x205d1e0) at mythplugin.cpp:159
> #39 0x000000000042ff1d in main (argc=3, argv=<optimized out>) at main.cpp:1658
>
>
> 9) I repeated (8) a couple more times.  Results were the same, including
>     doing yet another database backup each time (wasn't the previous
>     one good enough?).
>
> Since I ran the backend from an xterm, I do have what it output on
> stdout or stderr.  Nothing seems informative.  Just before the 100%
> CPU burn, it printed:
>    2013-03-31 23:11:30.187693 C  Database Backup complete.
>    2013-03-31 23:11:30.424095 C  Backed up database to file: '/mythspace3/recordings/mythconverg-1307-20130401030931.sql.gz'
>
> If it is useful, I could quote more.
>
> Note: MythWeb seems to work from another machine.  New recordings are
> happening.  So lots of this system is working.
>
> Why is this happening?  What can I do to fix it?
>

Looks like a problem with the nvidia driver from the backtrace. Maybe 
that's one of things that got updated? Looking at the BT it could be the 
old problem with ~/.ICEauthority that keep cropping up. I think what 
some users have done in the past is remove the ~/.ICEauthority file and 
rebooted but I don't know enough about it to know if that is the correct 
thing to do.

Paul H.