[mythtv-users] MythTV Installer Usability: An Analysis

[Dewey Smolka]

On 11/4/05, Chris Down <chris at alcor.co.uk> wrote:
> Fri, 4 Nov 2005  Dewey Smolka wrote
>
> >This still ignores the point that you're not using your appliance in
> >the recommended fashion. You could also complain that leaving your
> >coffee machine on overnight causes the caraffe to become uncleanable
> >and ruined. It may be true, but that is not how you're supposed to use
> >it.
>
> I am new to mythtv. Are you saying that mythtv is not intended for watching
> live tv? If so why have a prominent menu feature for this facility, why
> document it in the HOWTO etc? I realise that mythtv is a PVR however if a
> feature is included then it should at least function without causing a total
> system crash. I have not found any reference which says ".. don't use the
> Live TV option for more than x hours or your system may crash"
>
> I am sure a large number of users also use mythtv to watch live television.
>
> I don't think that you coffee machine analogy applies in this case :-)
>
> Just my 2 cents worth
>
> Chris Down

Sorry for the confusion. The coffee analogy applied to the OP who was
complaining about a Knoppmyth bug where it sets a ring buffer larger
than the partition designed to handle it, which will cause a crash.
The example he used was leaving Live TV on all night and waking up to
find the system in an unusable state.

I say this is not the recommended use because, while live TV works,
there are certain shortcomings that are structural and fundamental --
i.e. can't be fixed, at least in the current design.

One of these is that the ring buffer is not a standard recording, so
that when you change channels, for example, the ring buffer is erased
and restarted. This means that when channel surfing, you lose the
ability to rewind to a point behind when you switched channels. I
understand this is currently being addressed and that the ring buffer
will be redone in future versions.

Another problem is that there will always be a slight delay on Live
TV, and a delay of a few seconds when changing channels. This is
because MythTV has to instruct the tuner to change channels, initiate
recording in the ring buffer, then initiate playback of the ring
buffer. As the whole system is currently being redone, I don't know
how this will change in future versions, but I don't think the delay
in changing channels will go away. There is also a delay with any
digital cable or satellite system.

The prefered method for watching something 'live' is record it as a
normal recording and begin watching it immediately. Of course watching
it immediately eliminates the ability to skip ads, which is one of the
main reasons why people build a PVR in the first place.

As an example, I use MythTV to watch football games. If I start
watching the game at 1:00, I still have to sit through all the
nonsense. If I start recording at 1:00 but don't start watching until
2:30 or so, I can get almost the whole way through the game before
I've caught up with the live stream.

Of course the problem with sports is that the games rarely end on
time. This problem is solved by setting the 1:00 game to end 30
minutes late, and the 4:00 game to start -30 minutes early. With
multiple tuners this is less of a concern, but if you have a single
tuner like me, this addresses the problem when you want to watch games
on different channels.

Hope this helps