Unused tuner not being used for recording

[Verick42]

I am using one HdHomeRun Prime, and all three tuners are able to be used, and have been used in NextPVR, however, for some reason on Monday Better Call Saul refuses to record on an available tuner, and waits until another tuner is free, resulting in no post-padding for one of the earlier recordings, and no pre-padding for Better Call Saul.
Pre-padding: 1 minute, post-padding: 2 minutes

Recordings for the night:

8:00 - Superstore on 105 - 30 minutes
8:00 - Supergirl on 107 - 1 hour
8:00 - X-Files on 113 - 1 hour

9:00 - Lucifer on 113 - 1 hour
9:00 - Magicians on 676 - 1 hour

10:00 Better Call Saul on 697 - 1 hour
10:30 Samantha Bee on 664 - 1 hour

At 9:59, two tuners are in use, and should be in use until 10:02, at 9:59, Better Call Saul should use the third tuner that is idle since two tuners will be freed up at 10:02 and be available for the 10:30 recording, but the logs say that no tuner is available until 10:00 when it takes over the tuner recording The Magicians.

[johnsonx42]

Lucifer had been moved to the third tuner to accommodate padding, so that tuner was still busy at 21:59. The first tuner was still busy recording The Magicians, and the second tuner was idle at 21:59 but would be needed for Samantha Bee at 22:30. So there was no tuner available pre-pad Better Call Saul and record the entire show.

[Verick42]

Yes, but Lucifer and the Magicians stopped recording at 22:02, so either of those tuners would be able to record Samantha Bee, so there should be no reason to reserve a different tuner. Is that logic beyond the scheduler?

[sub]

Is that logic beyond the scheduler?

Yes. The scheduler covers a whole heap of scenarios, but not every scenario. In busy scheduling periods, when there there are lot of recordings happening, and others scheduled to start soon, and you're using live tv, it sometimes doesn't make the same choices that you would have.

It's complicated to cover every scenario, and I can see why most multi-tuner set top boxes dedicate a tuner to live tv, and don't worry about stuff like multi-record. Without these complications, it simplifies things a lot.

[johnsonx42]

Yes, but Lucifer and the Magicians stopped recording at 22:02, so either of those tuners would be able to record Samantha Bee, so there should be no reason to reserve a different tuner. Is that logic beyond the scheduler?

It can only move one recording on-the-fly; it can't go re-ordering the entire recording schedule. At the time it wanted a tuner to record "Better Call Saul" from 21:59 until 23:00, there wasn't any tuner available for the entire timeslot... it's not going to sit there and play "what if" games moving the next recording, and the next, and the next.

[Verick42]

Alright, thanks for the responses, I can just record a later airing to work around it.