[mythtv-users] LiveTV conflicts with scheduled recording - despite unused tuners on the same box!

[Michael T. Dean]

On 07/01/2009 11:15 PM, Jean-Yves Avenard wrote:
> 2009/7/2 Michael T. Dean:
>   
>> Because Myth is meant to record TV, and LiveTV is for people who haven't
>> figured out how to use a DVR.  :)
>>     
> I think that view of MythTV is very restrictive for no real reasons
> other than LiveTV is really lacking there.
>
> LiveTV isn't implicitly bad, there are many channels where recordings
> make no sense other than watching it live: sport and news channel
> being the 2 most obvious categories.
>   

I completely disagree.  Sport and news broadcasts should also be 
recorded.  "But," people say, "It makes no sense to record the 
news--it's not like I'll care about it next week."  Well, do you 
schedule your life so that you can start LiveTV exactly when the news 
show you like comes on?  Then why not schedule MythTV to record your 
favorite news show(s).  "But then I'll have to delete the old shows!"  
No, that's why Myth has the options allowing you to specify, "Delete 
oldest if this would exceed the max episodes," and, "Keep only one 
episode," or, "Keep at most <#> episodes."  And, with proper 
prioritization, you can also ensure that the recording won't prevent 
your seeing that great summer made-for-TV movie everyone's talking about.

"But," you may be thinking, "In this fast-paced world, the news is 
/constantly/ changing, so watching the news show I like with the anchor 
I like that started an hour ago means that I'll miss out on the latest 
breaking news."  So, why not schedule a news rule that records /every/ 
show on your favorite news channel (or every show between some specified 
hours--like 6pm to midnight).  Using the same, "Delete oldest..." and, 
"Keep at most..." settings and an extremely low priority, you basically 
have Myth always recording the most-current news for you--just in case 
you decide you want to watch it.

Oh, and, you'll be able to say, "I've seen no evidence that this type of 
scheduling causes mythbackend to eat memory," when people on the list 
try to tell you otherwise.

And, as for sports, schedule them to record, too.  /If/ you happen to be 
home when the game starts /and/ you happen to have all your snacks ready 
to go and all your friends showed up on time and ..., then go ahead and 
watch it as it records.  But, if you're running late at work and you 
realize that you still need to stop by the market to pick up some 
crudités and Vitamin water for the gang, you can send a quick text to 
your friends that they should show up 20-minutes later but not to worry 
because the game's recording so you can still watch it from the 
beginning (and skip some of the commercials).

To make it easier, think of LiveTV as, "Manual TV," whereas scheduled 
recordings are, "Automatic TV."  I.e. Myth takes care of starting 
scheduled recordings /for/ you, but /you/ have to go to the trouble of 
starting LiveTV when you want and tuning to the channel you want.  Used 
properly, LiveTV becomes, "Test your input connections TV."

Oh, and as for, "Channel surfers," try to convince them that the chances 
of them accidentally sitting down at exactly the right time to stumble 
upon the start of a show that's actually better than the couple hundred 
recorded shows they've told MythTV they actually /want/ to watch is 
probably close to the chances of their winning the lottery.  Usually, 
channel surfing ends with someone's starting to watch something that's 
"good enough" about 10-20 minutes after it started airing.

If those channel surfers spent that same channel-surfing time (or, 
likely a tiny percentage of that channel-surfing time) setting up 
recording schedules (i.e. do a movie search or a keyword search or a 
genre search--or even just browse the EPG), then watching some 
recording, they'd be able to sit down next time and watch /all/ of that 
show whose end they would have accidentally stumbled upon while channel 
surfing.

Once you learn to use a DVR, you'll be amazed at how freeing it is.  The 
point of a DVR is /not/ to record those shows that are so good you 
/know/ you'll watch them (or so good that you /know/ you want to keep 
them forever).  The point of a DVR is to record /every/ show you might 
/possibly/ want to watch so that you can watch it if you decide to.  The 
hardest part of getting to that point is learning not to feel guilty 
when you delete some show (or 50 episodes of a show--been there; done 
that; sorry DirecTV) when you decide you don't want to watch it.  
Recordings, they're not just for great shows, anymore.

>> If you want to ensure that Myth always chooses the
>> least-likely-to-be-used-for-recordings capture card for LiveTV, enable the
>> setting:
>>
>> Avoid conflicts between live TV and scheduled shows
>> f enabled, live TV will choose a tuner card that is less likely to have
>> scheduled recordings rather than the best card available.
>>     
> Unfortunately, this just doesn't seem work as expected in many cases.
>
> My backend has 5 tuners (DVB-T).
> I could be watching LiveTV on tuner 1, and the 4 others are free.
>   

If you're watching LiveTV on input 1 with inputs on 4 other cards free 
and a recording starts on input 1, you did not check that box.  The, 
"Avoid conflicts between live TV and scheduled shows," setting selects 
the least-preferred input for LiveTV (which, if you have 5 inputs, 
/should/ be the 5th one if you have your system properly 
configured***).  Recordings, however, will take the most-preferred 
capture card in all cases (regardless of the, "Avoid conflicts..." 
setting).  Therefore, if you're watching LiveTV on an input on card 1 
and a recording starts with 4 other cards free, you're either not using 
that setting or
  a) you entered LiveTV when 1 scheduled recording (that was on input 1) 
had finished but 4 others that ran concurrently with the 
recently-finished recording that was on input 1 are still in progress 
(i.e. all 4 other inputs are in use), or
  b) you've manually switched to another input.  For example, you may 
have switched inputs because only input 1 can pull the channel you're 
currently watching--in which case you probably should reorganize your 
cards so that the cards that can pull the largest subset of channels are 
most preferred, otherwise you're telling MythTV not to record some shows 
you want (as your most-preferred shows will record on the most-preferred 
inputs, so you may actually have conflicts due to the fact that it's 
recording a show that could be recorded on any of the 5 inputs but it's 
using the only input that's capable of pulling the channel that's airing 
a lower priority show).

*** Properly configured means that the most-preferred input has the 
lowest input ID and /none/ of the inputs have input priorities.  Note 
that no one should /ever/ mess with card/input priorities without first 
reading http://www.mythtv.org/docs/mythtv-HOWTO-12.html#ss12.6 , and, 
really, without reading all of section 12, to find out how messing with 
input priorities may actually mean you're telling MythTV not to record 
some shows you want to see.  Of course, after reading section 12, people 
would realize that there is /never/ a good reason to mess with input 
priorities and things actually work better when you just configure your 
system properly, so they'd instead configure their systems properly.  
But, regardless, the first step is reading section 12.

> One recording is now due on another channel and I get a message about
> either exit, record later or switch to that channel.
> This happens even with that particular configuration is set.
>
> So maybe, I'm just missing the logic behind "Avoid conflicts between
> live TV and scheduled shows", but it certainly doesn't seem to work
> sometimes: it asked me to change channels, when 4 other decoders were
> available.
>   

With, "Avoid conflicts between live TV and scheduled shows," Myth 
/always/ chooses the least-preferred input that's available when you 
start LiveTV.  So, if at the point that you enter LiveTV no other inputs 
are in use (by either other users' LiveTV sessions or scheduled 
recordings), you will get the least-preferred input.  If you have 5 
inputs connected, that means you won't get "kicked" from LiveTV until 
the 5th concurrent scheduled recording begins.

Without, "Avoid conflicts between live TV and scheduled shows," Myth 
will attempt to choose the most-preferred (assumed to be the 
highest-quality) available input that's local to the frontend in use for 
LiveTV.  If there are no available inputs locally, it will choose to use 
the most-preferred input available on some other system's backend.  In 
the simplest configurations, this means that /both/ LiveTV /and/ 
recordings try to use the best input, so /every/ recording that starts 
when you're watching LiveTV would get you kicked from LiveTV.

> The concept of "best recorder" is also a bit flawed I believe in what
> I believe is the most common mythtv setup: people with a dual tuner
> card, all tuners have the same priority ...
>   

Myth was not designed to only allow simplistic configurations.  Ask all 
the people in the US who have inputs (on dual-tuner or single-tuner 
cards) that record high-definition, digital ClearQAM and other inputs 
that record the S-Video (standard-definition, analog) output from cable 
set-top-boxes, if they believe some of their inputs are better than others.

> The "record later" is also a very US thing I believe. Very few
> channels I know actual do re-broadcast a program at a later stage,
> certainly not in Australia or France where I'm most familiar

Even in the US, a large number of shows (often the best shows--as those 
are the ones the networks tend to hate the most :) are never re-aired.  
"Record later," really means, "I'd rather miss the scheduled recording 
so I can see the end of this show that I started watching 20-minutes 
after it started and during which I'm wasting my life watching 
commercials all because I can't be bothered to choose to schedule 
recordings so I can watch TV on /my/ schedule--and, even though I have 4 
free inputs--I can't be bothered to exit LiveTV and re-enter it, which I 
wouldn't have to do if I had only enabled the setting, 'Avoid conflicts 
between live TV and scheduled shows'."  If the show MythTV is trying to 
record never re-airs, you /will/ miss the show if you choose, "Record 
later."  With a proper configuration and sufficient inputs, you 
shouldn't ever be faced with this dilemma, but the only way to be 
sure--in the face of multiple concurrent recordings--is to abstain from 
LiveTV completely.

Mike