[mythtv] Multiple tuner conflict resolution bug or feature?

[Bruce Markey]

Derek Atkins wrote:
> Bruce Markey <bjm at lvcm.com> writes:
> 
> [logic description elided]
> 
> I agree with the logic of trying to fit as many shows as possible in
> the best possible configuration....
> 
> 
>>But back to the situation being discussed. Let's say the
>>user has card 1 on a spiffy master that she loves and card
>>2 on a piece of it slave that she despises. On Tue Jan. 19
>>she has Nova "Secrets of the Crocodile Caves" ranked +3
>>showing at 8:00pm and repeated at 3:00am. American I-dull
>>ranked +5 at 8pm on Fox and The Tracy Morgan Show +1 at 8pm
>>on NBC. With the current logic she would get:
>>
>>8:00
>>card1: Idol
>>card2: Morgan
>>3:00
>>card1: Nova
>>
>>Perfect 8-).
> 
> 
> Sure, sounds great.  This is exactly how I would want it to
> behave...  However.....
> 
> 
>>If it tried to always choose the earliest showing:
>>
>>8:00
>>card1: Idol
>>card2: Nova
>>noRecord: Morgan
>>
>>Not so good. Even though Nova could record at a later time,
>>it out ranks Tracy Morgan which is only shown once. Also,
>>Nova was recorded on the crappy card rather than the good one.
> 
> 
> Let's stick with your example, but add a third card.  I've seen
> it end up with:
> 
> 8:00
> card1: Idol
> card2: Morgan
> card3: <empty>
> 3:00
> card1: Nova
> 
> It is *THIS* situation that I'm asking about.

I know but using an example where there wouldn't be a problem
doesn't make the problem go away. 

> I see no reason to
> leave an encoder blank like this (especially when they are all
> equivalent cards).

But that doesn't mean that everyone else has equivalent cards.
Many people have a PVR plus some bttv cards or a stereo card
and a mono card etc. I have equivalent cards but not equivalent
signal quality at each of the drops. Multiple backends could
have different CPUs, disk space, local disk vs NFS, etc.

> Why didn't it end up with card3: Nova?...

Because of the logic above (deleted). After the initial layout
it needs to remove multiple showing of the same episode regardless
of any of those showings overlapping other record candidates.
If there are three showings with no conflicts, it still needs
to remove two of them before continuing.

With three cards, the same situation would come up if there
were four overlapping shows and so on. So what if you wanted
to use as many cards as possible unless there were too many
shows then move one of them. Move which one if more than one had
more than one showing? And what if those other showings overlapped
other shows? What if there are three cards and five shows and
three of those have other showings? It could quickly become a
very complex recursive game of tetris trying to shuffle and
reshuffle things to meet an ambiguous best fit. This would keep
all showings of repeated episodes in limbo until something
finally decides that this showing of this show goes here then
revisits the timeslots for the other showings and so on.

If you do see a situation like this example and decide that
you want to grab the 8pm Nova, simply find it on the conflicts
page, then press Enter, Down, Enter. The 8pm showing will be
assigned to a tuner and the 3am showing will change status to
"O" (then "P" after 9pm =).

I think the default behavior does the best job of recording
the most shows on the best card and recording the largest amount
of different titles during crunch time. However, with the
addition of "do record" and "don't record" overrides, no record
status, and positive and negative pre- and post-roll (take that,
NBC) you really have a lot of power to slice and dice now. You
can make these little personal choices and the scheduler will
do the right thing around them. Your addition of ignoring
duplicates for single records helps too (however, some work
still needs to be done to make it easier to setup a single
record that overlaps a recurring record).

--  bjm