[mythtvnz] Mythbuntu

[Stephen Worthington]

On Thu, 7 Jul 2011 15:06:18 +1200, you wrote:

>On Thu, Jul 7, 2011 at 1:30 PM, AlanP <alan.p at orcon.net.nz> wrote:
>> Has anyone had a play with the most recent release? Any major issues with
>> it? I'm currently running R5.5 of KnoppMyth and am thinking of doing a
>> fresh install of MythBuntu.

>mythbuntu 11.04 was full of problems when it came out. I recommend
>10.04 plus update to myth 0.24-fixes via mythbuntu-repos.

Unless you have a card that you need the latest kernel for, that is
probably the best advice.  I needed the 2.6.36+ kernels to make my
TeVii S470 DVB-S2 card work.  Things have settled down now, but there
are still some niggling things related to the kernel and drivers that
cause problems, eg the playback freezing for a second or two due to
audio buffering setup problems, or problems with lirc on my mother's
MythTV box with her Hauppauge TD-500's remote.

MythTV 0.24-fixes also has a rare but nasty problem.  If you are
recording from many channels at the same time, it is possible to get a
deadlock condition in the scheduler where it fails to start any new
recordings and the frontend has trouble accessing the backend.
Unfortunately, I get this condition occasionally, due to having three
DVB-T tuners plus Sky from an S-Video input on my PVR-500, all
recording at the same time.  I am not sure if it happens with 0.24
without fixes, but I never had it happen until I updated to
0.24-fixes.  I think I need to be recording more than one program from
the same multiplex as well as having all tuners scheduled in order to
trigger the bug.  If you have the deadlock happen, it can still be
recording programs that started before the deadlock, and they will
record properly, but the only way to get it to start new recordings is
to restart the backend (which will kill the recordings that are
working at the time).  The symptom of this bug is this in your
mythbackend.log:

  Protocol version check failure.
  The response to MYTH_PROTO_VERSION was empty.
  This happens when the backend is too busy to respond,
  or has deadlocked in due to bugs or hardware failure.

I have found a bug report which appears to be this problem, and it
does not seem to be fixed yet, but when it is it looks as though the
fix will be backported to 0.24-fixes:

  http://code.mythtv.org/trac/ticket/9704

If I know I am going to have the deadlock (due to it having happened
the week before recording the same combination of programs), I can
prevent it from happening by not recording from one DVB-T multiplex at
the problem time.  That is OK for me, as I can get my Mother's MythTV
box to record that multiplex for me and then use MythExport to
transfer the recordings to my box.  But the first time I get the
deadlock it is a big pain, and I have had to go and get missing
recordings from the net.

So it might pay to stay with MythTV 0.24 without fixes if you have as
many tuners as I have, in case this bug came along after that.  0.24.1
probably has the bug.