Another question about Pi 4 as backend

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MikeB2013
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Joined: Mon Jul 25, 2016 4:16 pm
Great Britain

Re: Another question about Pi 4 as backend

Post by MikeB2013 » Mon Mar 30, 2020 8:35 am

Effect of "--cpu=cortex-a7 --arch=armv7 --extra-cflags=-mfpu=neon --extra-cxxflags=-mfpu=neon" for mythtv 30 is unknown, should only be used from mythtv 31 (needed due to total playback rewrite from that used in prior versions such as mythtv 30).

Just in case you have not seen some earlier posts:

1. There is a script (pi-mythbackend-helper.sh) which does all of the configuration of mythtv-light (with default pi user) to allow it to be used as a full mythtv backend (mythtv-light includes the basic components but does not install or setup other programs such as apache, xmltv, php etc).
See post viewtopic.php?f=46&t=3232#p15773

2. There is another script (pi-SDtoHD-helper.sh) which automates movement of Raspbian Buster root from microSD card to an external disk.
See post viewtopic.php?f=46&t=3232&start=15#p15884

3. There are also a couple of other scripts relating to mythtv-light 31 (not yet fully available) only, as it runs from Console (no Desktop)
run_mythfrontend.sh starts mythfrontend.
run_mythsetup.sh which starts mythtv-setup.

script pi-setup_mythtv_31.sh is a work in progress

The latest versions of these scripts are now available from my github repository at https://github.com/MikeB2013/pi-utils

Mike

jeff_mythtv
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Re: Another question about Pi 4 as backend

Post by jeff_mythtv » Wed Apr 01, 2020 1:03 pm

Mike,

I compiled the v31, everything works, including the commercial flagging. Absolutely happy with this cut, very clean. And your script saved me a lot of time, thank you.

I think I am going to test this for the next few days then will migrate my v26.4 (2015) over. I think the only table I need to covert is the recorded table, v31 has three extra fields. It should be OK.

Very happy with this release...... Made a strong case to upgrade.

Thanks again.

MikeB2013
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Posts: 511
Joined: Mon Jul 25, 2016 4:16 pm
Great Britain

Re: Another question about Pi 4 as backend

Post by MikeB2013 » Wed Apr 01, 2020 2:56 pm

jeff_mythtv wrote:
Wed Apr 01, 2020 1:03 pm
Mike,

I compiled the v31, everything works, including the commercial flagging. Absolutely happy with this cut, very clean. And your script saved me a lot of time, thank you.

I think I am going to test this for the next few days then will migrate my v26.4 (2015) over. I think the only table I need to covert is the recorded table, v31 has three extra fields. It should be OK.

Very happy with this release...... Made a strong case to upgrade.

Thanks again.
Interesting that commercial flagging is now working. I guess it is something to do with the playback rewrite in mythtv 31. The original trac ticket was done before some of the more recent changes. I need to revisit mythtv 31 on my Pi4.

As far as the upgrade from v26.4 is concerned, any required table upgrades (and there are more than just recorded table) should happen automatically and not require any user action. All I normally do is when rebuilding a system is to run mythconverg_backup script to create a snapshot of the database on the old system and then restore it using mythconverg_restore on the new system which many also have an operating system upgrade as well as installing a new version of mythtv. Any schema changes are automatically applied as soon as mythbackend/mythtv-setup is started. Note that the automatic upgrade can take a while and is silent in operation. More information on mythconverg_backup and mythconverg_restore is at https://www.mythtv.org/wiki/Database_Backup_and_Restore

If at all possible keep hostname on the new system, the same as the old.

knappster
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United States of America

Re: Another question about Pi 4 as backend

Post by knappster » Thu Apr 02, 2020 5:18 pm

jeff_mythtv wrote:
Wed Apr 01, 2020 1:03 pm
Mike,

I compiled the v31, everything works, including the commercial flagging. Absolutely happy with this cut, very clean. And your script saved me a lot of time, thank you.

I think I am going to test this for the next few days then will migrate my v26.4 (2015) over. I think the only table I need to covert is the recorded table, v31 has three extra fields. It should be OK.

Very happy with this release...... Made a strong case to upgrade.

Thanks again.
It is encouraging that commercial flagging is working for you in v31. I would like to retire some of my old hardware and offload this to another pi if possible. Do you happen to know if your recordings are in MPEG2 or h264 format? Mike's trac ticket indicates that it was not an issue for h264 even on v30. I use the standard HDHomeruns, but I believe the HDHomerun Extend, for example, transcodes to h264 on the fly.

jeff_mythtv
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Re: Another question about Pi 4 as backend

Post by jeff_mythtv » Thu Apr 02, 2020 9:26 pm

The recordings are in MPEG2, I think.

When I compiled, I noticed h264 was not supported, because there is no h264 driver installed. I don't use mythtranscode either. My front end is a pi running OpenELEC with myth-dvr point to this pi4. Everything has been fine. I don't feel any different compared to running against the current production box. I am surprised and relieved the pi4 can do the job sufficiently.

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