[mythtv-users] switching mythfilldatabase from being run by mythbackend to systemd timer?

[Stephen Worthington]

On Sun, 29 May 2022 07:31:33 -0400, you wrote:

>I built a test FE/BE combo on an old PC using Archlinux and  MythTV v32.
>And for that to work properly I had to implement my mythfilldatabase
>automation via a systemd service/timer. Because I wanted twice a day
>running of mythfilldatabase, I used the following in my .timer:[Unit]
>
>[Timer]
>OnCalendar=05:10:00
>OnCalendar=17:10:00
>Persistent=true
>
>I was thinking about changing to the service/timer method for my production
>backend built on Ubuntu 22.04. Other than unchecking the "use automatic
>mythfilldatabase" box in mythtv-setup -> General, are there any other
>considerations for making the switch??
>
>Jim A

You need to check your existing settings for the mythfilldatabase
command line, to ensure that you are using the same settings.  It is
disconcerting to have the channels change on you because
mythfilldatabase changed them when it did not do that previously due
to using the --only-update-guide option.

Deciding when to download can have some implications, but it did
anyway with mythbackend starting the downloads.  It depends a bit on
where you are getting your EPG from.  If you are downloading it from
the Internet, then it possible for the server to get overloaded by too
many downloads at the same time each day, so their EPG download
software may actually be introducing a random delay to spread the
load, or assigning you a download timeslot.  So check with them to be
sure.  If you had mythfilldatabase being run automatically by
mythbackend at say 05:00 every day, that may have just been the time
that the download was triggered, and it actually downloaded somewhat
later.

If you are collecting the EPG yourself from the EPG broadcast, then
the timing does not matter, but you probably want to do some testing
to work out when the broadcast EPG gets updated, so you can capture it
shortly after the update time.  To do that, you need to do regular
captures over 24 hours (say every half hour), and keep a copy of the
data each time so you can compare them and see when it changes.  It is
fairly typical for broadcast EPG to only be updated once or twice a
day.  If you are really lucky, there may be an update if they change
their programming at the last minute, or if some live programme runs
long.