Spurious "encoders" reported by mythbackend

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knutsondc
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Spurious "encoders" reported by mythbackend

Post by knutsondc » Wed Jun 24, 2020 6:38 pm

Hello all,

I've run across a curious phenomenon while running MythTV 31/fixes. Occasionally Mythweb's backend status page reports the presence of numerous encoders in excess of the four I actually have installed. Just a few moments ago, the backend reported encoders 1 through 4, which is correct, and encoders 45 through 58, which is not. You can see that this has happened several times because the backend increments the encoder number by one for each encoder "installed," even if lower-numbered encoders have since been deleted. When these spurious encoder numbers appear, I use the CaptureCard API to delete them and they disappear when mythbackend gets restarted. The next time the bogus encoders get reported, they number up from the last previous encoder number mythbackend assigned.

These bogus "encoders" do not seem to interfere with MythTV's functionality at all and they are easily deleted, but I am curious about how and why they get created. Does anybody have an idea? Thanks!

Darron

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bill6502
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Re: Spurious "encoders" reported by mythbackend

Post by bill6502 » Wed Jun 24, 2020 9:44 pm

https://www.mythtv.org/wiki/VBox#Multirecord explains one reason. Which
won't explain it if you don't user VBox.

In the DB, the cardid column in the capturecard table is set to auto_increment, so
the values will always go up.

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kmdewaal
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Re: Spurious "encoders" reported by mythbackend

Post by kmdewaal » Wed Jun 24, 2020 10:22 pm

I also think that this is the so-called Multirec feature, recording more than one program from one transport stream multiplex using one physical tuner. Previously, the Multirec feature was enabled when selecting a "Max Recordings" value of more than 1. This still works, but if the "Schedule as Group" option, also in the "Input Connections" page, is enabled, and it is enabled by default, additional capturecard entries are created when needed.
If you want predictable encoder numbers then you can set Max Recordings to e.g. 4 for each capture card immediately after creating the capturecard. Then you have encoders 1 to 4 for the first capturecard, 5 to 8 for the second capture card etc.

knutsondc
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Re: Spurious "encoders" reported by mythbackend

Post by knutsondc » Thu Jun 25, 2020 2:24 pm

Thanks, bill6502 and kmdewaal, your explanations are very helpful! I'm a little less puzzled now.

Darron

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