Can someone explain the "EPG update window" setting?

Mathieu Gouin

Hello,

In tvheadend, under Configuration -> Recording, there is an option: "EPG update window".

From the online help, it says:

EPG update window : Maximum difference between event start times when the EPG event is changed. TVHeadend uses a fuzzy match logic (using title, start times, duration, episode) to check when the event was changed

Recently, one of my scheduled movie recording was marked as failed with description: time missed. I was wondering if this is related to this setting?

Is it related to the update of a program EPG data? What happens if it changes before the time windows? After the time window?

I would greatly appreciate some light be shed on this obscure options...

Thanks a lot in advance!

Mathieu

mpmc

Mathieu Gouin wrote:
> Hello,
>
> In tvheadend, under Configuration -> Recording, there is an option: "EPG update window".
>
> From the online help, it says:
>

> EPG update window : Maximum difference between event start times when the EPG event is changed. TVHeadend uses a fuzzy match logic (using title, start times, duration, episode) to check when the event was changed

Basically, when the epg data gets parsed Tvheadend will check for differences between the new epg data & the data it already has. If the data for any matching scheduled event (upcoming recordings) changes [within the new data], it'll update the entry; As long as the change occurred within the "update window" time frame. This is how I understand it works anyway :p

>
>

> Recently, one of my scheduled movie recording was marked as failed with description: time missed. I was wondering if this is related to this setting?

I highly doubt it, "time missed" can mean a lot of things (see the Help for DVR to see a list).

>
> Is it related to the update of a program EPG data? What happens if it changes before the time windows? After the time window?
>
> I would greatly appreciate some light be shed on this obscure options...
>
> Thanks a lot in advance!
>

> Mathieu

Mathieu Gouin

Hello Mark,

Thanks for the response.

Based on your explanation, would you recommend setting this value to a very high number in order to update all events? The default setting was set to 24h, but I fear this is too short.

Would you mind sharing what value you have?

Thanks!

mpmc

Mathieu Gouin wrote:
> Hello Mark,
>
> Thanks for the response.
>
> Based on your explanation, would you recommend setting this value to a very high number in order to update all events? The default setting was set to 24h, but I fear this is too short.
>
> Would you mind sharing what value you have?
>

> Thanks!

It depends on how you've setup your EPG, the intervals in which Tvheadend is set to grab the data.. With the OTA grabber 24 hours should be enough (It's set by default to grab at 02:04 & 14:04 daily, and it'll grab each time you tune to a mux). For external grabbers, xmltv for example, you may want to increase it (by default it is set at 00:04 and 12:04 daily).

Have a play & see what works best for you.

Mathieu Gouin

Hi Mark,

> Have a play & see what works best for you.

That's the problem I have with this setting. How can I tell it's working as expected?

For the record, I'm using xmltv. I download my EPG guide daily at 04:00.

Thanks again for your help!

Mathieu

Mathieu Gouin

Recently, I experienced a problem which seems to be related to this setting.

I had programmed a recording for an upcoming movie that I wanted to watch. Let's say the movie was originally planned to air in 5 days at 3pm. That's what my downloaded guide (xmltv) was showing at this time. From tvheadend web interface, I selected the movie I was interested in and clicked "Record Program". At this point tvheadend created a one-time recording entry at the specified time, date & channel. So far so good :)

Meanwhile, the channel changed its schedule and the movie in question slipped from 3pm to 4pm instead. My nightly download of the xmltv EPG got this update before the movie started (let's say 2 days before).

However, my recording was for the original 3pm instead of the updated 4pm.

Sorry, long story, but my question is: should tvheadend have updated the recording entry following a change of schedule? Could this be related to the "EPG update window" setting?

I know that having created an "auto-rec" instead of a one-time recording would have definitely updated to the new time. However, I'm in the impression that this is not the best way to schedule a one-time recording...

Thanks again!

mpmc

Was the change reflected in the EPG data? How did tvh list the change? You can tell by finding the film in the EPG tab & checking the start/end times, look out for duplicates too. If you see anything strange. Like two entries listed for the same movie but different times it could be a bug with tvheadend or the data source.

If you only see one entry and that has the correct dates etc, please open a bug (issue). Attach screenshots & provide xmltv data etc.

Mathieu Gouin

> Was the change reflected in the EPG data?

Yes!

> How did tvh list the change?

When I noticed the problem, I was by chance looking at Kodi Guide window which is in fact showing the EPG data from tvh. At this point, I saw the movie at the new time and the show the hour before with the timer symbol next to it. I did not have the reflex to have a look also in tvh web guide.

At least, can you confirm that in a situation similar to what I described in my previous post, tvh should have updated the timer entry with the new start time?

This kind of problem is hard to debug as it has a low occurrence frequency... I'll try to get more debug data next time.

Thanks in advance.

mpmc

Mathieu Gouin wrote:
> > Was the change reflected in the EPG data?
> Yes!
>
> > How did tvh list the change?
> When I noticed the problem, I was by chance looking at Kodi Guide window which is in fact showing the EPG data from tvh. At this point, I saw the movie at the new time and the show the hour before with the timer symbol next to it. I did not have the reflex to have a look also in tvh web guide.
>

> At least, can you confirm that in a situation similar to what I described in my previous post, tvh should have updated the timer entry with the new start time?

In theory it should've yes. but I can't be certain that the epg update window applies to xmltv data, I would've thought it would. What value did you set the update window to?

>
> This kind of problem is hard to debug as it has a low occurrence frequency... I'll try to get more debug data next time.
>

> Thanks in advance.

Mathieu Gouin

> In theory it should've yes. but I can't be certain that the epg update window applies to xmltv data, I would've thought it would. What value did you set the update window to?

48 hours.

The movie only slipped by 1 hour, so I assume it should have been updated.

I'm currently looking at the github code to see if I can better understand this...

Thanks again!

Mathieu Gouin

According to what I could understand from the github code, this setting is related to the difference from the original start time to the new start time in absolute (forward or backward in time).