[mythtv-users] intermittent mythbackend hang EIT?

[Stephen Robertson]

2009/3/24 Stephen Robertson <stephengrobertson at gmail.com>
>
> 2009/3/24 David Watkins <watkinshome at gmail.com>
>>
>> > No error type from QSqlError?  Strange...
>> > 2009-03-24 02:26:38.903 DB Error (Looking up chanID):
>> > Query was:
>>
>>
>> That looks like what I remember seeing when mythbackend starts and
>> can't connect to the mysql server.
>>
>> Is it possible that your database connection has died, rather than
>> there being something wrong with the query?
>>
>> Just a thought.
>
> Possibly.  Certainly the times when it has not fallen over completely then the frontend still knows that the backend is there, but the watch recordings screen, for example, is empty.  In this instance the backend stopped and was restarted by monit and everything seemed to carry on fine
>


 Well the crash has happened again this time there is a bit more in
the mythbackend log.  Mythbackend died and was restarted by monit.
Again it looks as though it happens when an EIT scan is in progress,
nothing was being played back or recorded at the time.

Does anyone have any clues as to how to diagnose this any further?

 Thanks
 Stephen

 MythTV Version   : 20239
 MythTV Branch    : branches/release-0-21-fixes
 Library API      : 0.21.20080304-1
 Network Protocol : 40
 Options compiled in:
  linux profile using_oss using_alsa using_jack using_backend
using_dbox2 using_dvb using_firewire using_frontend using_hdhomerun
using_iptv using_ivtv using_joystick_menu using_libfftw3 using_lirc
using_opengl_vsync using_opengl_video using_v4l using_x11 using_xrandr
using_xv using_xvmc using_xvmcw using_xvmc_vld using_glx_proc_addr_arb
using_bindings_perl using_bindings_python using_opengl
using_ffmpeg_threads using_libavc_5_3 using_live


 Mythbackend.log:(Enabled verbose msgs: important general eit)
 2009-03-25 12:11:03.693 EITScanner (1): Added 1 EIT Events
2009-03-25 12:11:03.694 EITScanner: Rate limiting reschedules..
> 2009-03-25 12:13:05.184 EITCache: Wrote 1 modified entries of 150 for channel 1035 to database.
> 2009-03-25 12:13:05.808 EITScanner (2): Now looking for EIT data on multiplex of channel 30
> 2009-03-25 12:13:05.811 EITCache: Pruning all entries that ended before UTC 2009-03-24T12:18:33
> 2009-03-25 12:13:05.911 EITCache: Deleting old cache entries from the database
> 2009-03-25 12:13:07.496 EITScanner (2): Started passive scan.
> 2009-03-25 12:13:08.756 EITHelper: Added 2 events
> 2009-03-25 12:13:09.204 EITHelper: Added 2 events
> 2009-03-25 12:13:09.669 EITHelper: Added 3 events
> 2009-03-25 12:13:10.093 EITHelper: Added 1 events
> 2009-03-25 12:13:10.517 EITHelper: Added 1 events
> 2009-03-25 12:13:12.139 EITHelper: Added 1 events
> 2009-03-25 12:13:12.555 EITHelper: Added 1 events
> 2009-03-25 12:13:12.970 EITHelper: Added 1 events
> 2009-03-25 12:13:50.119 EITCache: Wrote 2 modified entries of 236 for channel 1011 to database.
> 2009-03-25 12:13:50.135 EITCache: Wrote 1 modified entries of 191 for channel 1018 to database.
> 2009-03-25 12:13:50.141 EITCache: Wrote 2 modified entries of 273 for channel 1019 to database.
> 2009-03-25 12:13:50.153 EITCache: Wrote 1 modified entries of 254 for channel 1025 to database.
> 2009-03-25 12:13:50.160 EITCache: Wrote 2 modified entries of 293 for channel 1029 to database.
> 2009-03-25 12:13:50.165 EITCache: Wrote 1 modified entries of 150 for channel 1035 to database.
> 2009-03-25 12:13:50.190 EITCache: Wrote 2 modified entries of 172 for channel 1083 to database.
> 2009-03-25 12:13:50.211 EITCache: Wrote 1 modified entries of 8 for channel 5476 to database.
> 2009-03-25 12:13:50.779 EITScanner (1): Now looking for EIT data on multiplex of channel 30
> 2009-03-25 12:13:50.781 EITCache: Pruning all entries that ended before UTC 2009-03-24T12:18:56
> 2009-03-25 12:13:50.881 EITCache: Deleting old cache entries from the database
> 2009-03-25 12:13:51.608 EITScanner (1): Started passive scan.
> 2009-03-25 12:14:00.602 DB Error (Looking up chanID):
> Query was:
>
> No error type from QSqlError?  Strange...
> *** glibc detected *** /usr/bin/mythbackend: munmap_chunk(): invalid pointer: 0x0822daf0 ***
> ======= Backtrace: =========
> /lib/tls/i686/cmov/libc.so.6(
> cfree+0x1bb)[0xb5bd061b]
> /usr/lib/libstdc++.so.6(_ZdlPv+0x21)[0xb5d97b11]
> /usr/lib/libqt-mt.so.3(_ZN11QStringData10deleteSelfEv+0x2e)[0xb665c3ba]
> /usr/lib/libmyth-0.21.so.0(_ZN12MSqlDatabase12KickDatabaseEv+0x55)[0xb6c02905]
> /usr/lib/libmyth-0.21.so.0(_ZN9MSqlQuery7InitConEv+0x5d)[0xb6c063bd]
> [0xb351a188]
> [0xb351a188]
> [0xb351a160]
> ======= Memory map: ========
> 08048000-0815b000 r-xp 00000000 08:01 3943533    /usr/bin/mythbackend
> 0815b000-0815c000 rw-p 00113000 08:01 3943533    /usr/bin/mythbackend
> 0815c000-08426000 rw-p 0815c000 00:00 0          [heap]
> a9400000-a9464000 rw-p a9400000 00:00 0

Lots of memory map deleted!!


> b7f1e000-b7f22000 rw-p b7f1e000 00:00 0
> b7f23000-b7f2c000 r-xp 00000000 08:01 1476594    /lib/tls/i686/cmov/libnss_files-2.7.so
> b7f2c000-b7f2e000 rw-p 00008000 08:01 1476594    /lib/tls/i686/cmov/libnss_files-2.7.so
> b7f2e000-b7f2f000 rw-p b7f2e000 00:00 0
> b7f2f000-b7f31000 rwxp 00000000 00:0e 971        /dev/zero
> b7f31000-b7f33000 rw-p b7f31000 00:00 0
> b7f33000-b7f34000 r-xp b7f33000 00:00 0          [vdso]
> b7f34000-b7f4e000 r-xp 00000000 08:01 1460363    /lib/ld-2.7.so
> b7f4e000-b7f50000 rw-p 00019000 08:01 1460363    /lib/ld-2.7.so
> bfabf000-bfad4000 rwxp bffeb000 00:00 0          [stack]