[mythtv-users] how to influence tuner choice

[Bruce Markey]

Peter Abplanalp wrote:
> hi all,
> 
> i have a master backend and 2 slave backends/frontends each with a
> tuner (1,3,4).  i've read that myth will try to use the tuners in the
> order that they were added but it looks like myth is skipping tuner 3
> which coincidentally is the lowest on disk space.  i was wondering if
> there is a way to influence the choice of tuner.  the problem is that
> the machine with tuner 1 is getting low on space but tuner 4 has a
> ton of space.  tuner 1 is also the one hooked to a cable box so i'd
> like to save the space on that box to record things that only it can
> record.  the other 2 just do the analog channels and could easily
> record all the main network shows while tuner 1 is the only one that
> can record hbo and the like.  can i influence myth to use tuner 4
> more often somehow without removing and adding the cards again?  or,
> will myth do this by itself once the space on the box with tuner 1
> gets low?  i'm down to about 10gb and it is xfs and the threads
> recently about fs type have got me a little jittery; although, i've
> never had a problem with xfs in the 2 years i've been running myth.
> i've tried to search the list and google but didn't get any results.

http://www.mythtv.org/docs/mythtv-HOWTO-12.html#ss12.6

It is actually the input number rather than the card number
that determines the order. You should add cards and their
inputs at the same time so the card order is the same. However,
a quick'n'dirty solution would be to remove the input on card 3
then re-add it so that has a new, highest number. In mythtv-setup
on the card 3 host, go to Input connections, choose the current
input, change it's "Video source:" to "(None)" then Finish.
Choose this input again and change it from None back to the
real video source and Finish. This will now be the last input.

You can use "Input priority" on that page to influence priority
for scheduling but this behaves differently than the order of
the inputs. Please see the HOWTO subsection for "Input Priority".
Note the diagrams that show how this will cause shows the be
postponed in order to use the better input. This might be what
you want but based on your situation, I wouldn't think so. Even
if you do want to do this temporarily or permanently, you are
still better off renumbering your cards correctly for the long
haul.

Renumbering your cards isn't as daunting as you may think. I just
did it for a two host test environment in under two minutes
(mostly waiting for mythtv-setup to startup =). You do not want
to remove your video sources, channels, rules, listings data and
all of this stuff is safe. By deleting all cards, the card table
and the input table are emptied and reset to zero. you can then
add the cards and associate your existing video sources with
the appropriate inputs.

- Stop all myth programs

- Backup your database if for no other reason than reference.
http://www.mythtv.org/docs/mythtv-HOWTO-23.html#ss23.5

- Run mythtv-setup on you master

- Under "2. Capture cards", select "(Delete all capture cards)".
Note: this is not the same as the "...on hostname)" version which
does not affect cards on other hosts and does not reset the
numbers. Use "(Delete all capture cards)".

- Add your cards and inputs in your order of preference. Note
that card 1 doesn't have to be the master. My card 1 is on a
slave in another room. Run mythtv-setup on the host of your
card that you want to be first.

- Assuming that card 1 will be on the master and you are still
on the Capture cards page, select "(New capture card)", Finish.

- Go to "4. Input connections", select your active input, choose
your existing video source, Finish.

- Rinse and repeat adding your card and inputs in order.

- Restart your slave and master backends.

Go to your Upcoming Recordings page in mythfrontend and you
should see that all of your shows are scheduled to record. I'm
going to assume that your card 1 will be 1 again, old card 4
is now 2 and 3 is 3 again. You should see that most things are
assigned to 2 rather than 3 and 3 is only used when 2 is busy.

If there are still too many things assigned to 3 before you
can clear more space, you many want to run mythtv-setup on the
card 3 host and set that input to priority -1. This will move
things from card 3 to later showings on card 2 when possible.
Once you do have more space on the card 3 hosts, you may want
to set the priority back to 0 so that things will again record
at the earliest time possible.

I hope this helps.

--  bjm