[mythtv-users] mythbackend hanging with busy disk

[Jeffrey Ratcliffe]

My mythbackend hangs from time to time with a busy disk.

It is not reproducible, but happens every couple of days.

When it happens, I cannot log in via ssh, and mythweb is also
unresponsive. The one time I happened to be already logged in via ssh,
htop showed that it was not CPU-bound.

Therefore, I don't have any other option but to pull the plug, count
to ten, and reboot. Afterwards, looking at /var/log/syslog and the
list of recorded programs, I see a 0-length recording and:

Apr  6 15:53:32 pan mythbackend: message repeated 102622 times: [
mythbackend[2403]: N Scheduler scheduler.cpp:2771 (HandleIdleShutdown)
Blocking shutdown because a recording is due to start soon.]
Apr  6 15:53:37 pan mythbackend: message repeated 11096 times: [
mythbackend[2403]: N Scheduler scheduler.cpp:2771 (HandleIdleShutdown)
Blocking shutdown because a recording is due to start soon.]
Apr  6 15:53:45 pan mythbackend: message repeated 20943 times: [
mythbackend[2403]: N Scheduler scheduler.cpp:2771 (HandleIdleShutdown)
Blocking shutdown because a recording is due to start soon.]
Apr  6 15:54:37 pan mythbackend: message repeated 120254 times: [
mythbackend[2403]: N Scheduler scheduler.cpp:2771 (HandleIdleShutdown)
Blocking shutdown because a recording is due to start soon.]

This may be a red herring, but why would the message be repeated so many times?

In /var/log/mythtv/mythbackend.log, I see messages like:

Apr  6 15:53:32 pan mythbackend: mythbackend[2403]: W TVRecEvent
recorders/dvbchannel.cpp:386 (CheckOptions)
DVBChan[7](/dev/dvb/adapter0/fr
ontend0): Selected fec_inner parameter unsupported by this driver.
Apr  6 15:53:37 pan mythbackend: mythbackend[2403]: E TVRecEvent
recorders/dvbchannel.cpp:1107 (GetUncorrectedBlockCount)
DVBChan[7](/dev/dvb/adapter0/frontend0): Getting Frontend uncorrected
block count failed.#012#011#011#011eno: Operation not supported (95)
Apr  6 15:53:37 pan mythbackend: mythbackend[2403]: W TVRecEvent
recorders/dvbsignalmonitor.cpp:97 (DVBSignalMonitor)
DVBSigMon[7](/dev/dvb/adapter0/frontend0): Cannot count Uncorrected
Blocks#012#011#011#011eno: Operation not supported (95)
Apr  6 15:53:45 pan mythbackend: mythbackend[2403]: N DVBRead
recorders/dtvsignalmonitor.cpp:367 (HandlePMT)
DTVSigMon[7](/dev/dvb/adapter0/frontend0): PMT says program 4326 is
encrypted
Apr  6 15:54:37 pan mythbackend: mythbackend[2403]: I DVBRead
mpeg/mpegstreamdata.cpp:1979 (ProcessEncryptedPacket)
MPEGStream[7](0x7f0000130f18): PID 0x28c status: Encrypted

Does this mean that it tried to record an encrypted program, and it
hit the disk until I pulled the plug two hours later? The channel it
should have recorded then is not encrypted.

What does "program 4326" mean?

Concerned that I had some old channel info in the database, yesterday
I deleted the transport and channel tables with:

mysql -umythtv -pxxxxxxxx -e"DELETE from mythconverg.channelscan_dtv_multiplex;"
mysql -umythtv -pxxxxxxxx -e"DELETE from mythconverg.channel;"

and then rescanned for channels.

Any ideas?

Regards

Jeff