[mythtv-users] Job priority within Myth's job queue

[Michael T. Dean]

On 04/10/2006 04:33 PM, G. Panula wrote:
> Is there a way to give Commercial Flagging jobs priority over 
> Transcoding jobs within Myth's job queue?
>   

In mythtv-setup (on page "Job Queue (Global)"):

Run Transcode Jobs before Auto-Commercial Flagging
If set, if both auto-transcode and auto commercial flagging are turned 
ON for a recording, transcoding will run first, otherwise, commercial 
flagging runs first.

(Note, however, that if you specify transcode before commflag and 
real-time commflagging, your commflagging won't be real-time because it 
still waits until after the transcode, which occurs after recording.)

> Here is the scenario...
> Front-end has the tuner card which writes to a Back-end.
> Front-end is only allowed to process jobs(e.g. commercial flagging) from 
> the queue only during the wee hours of the morning when no one is likely 
> to be watching tv.
> The Back-end processes jobs 24x7.
> "Real-time" commercial flagging is enabled.
> Commercial flagging and Transcoding are enabled for all recordings.
>
> When recording a line-up of programs say
> 5:30pm That 70s show
> 6:00pm The Simpsons
> 6:30pm The Simpsons
>
> Front-end starts recording "That 70s show" and adds a commercial 
> flagging job to the queue.  Back-end sees the job and starts it.
>
> Then the front-end finishes recording "That 70s show", adds a transcode 
> job, starts recording the first "Simpsons" and adds a commercial 
> flagging job for it.
>
> The *problem* is the transcoding job is the next job in the queue and 
> the back-end faithfully starts working on it.  Even if I have the 
> back-end only checking the queue every 5 minutes, it still picks the 
> transcoding job first.  I think jobs are just processed on age; oldest 
> one first aka FIFO(First In First Out)
>
> Ideally the commercial flagging jobs should have a higher priority than 
> transcoding job or at least an option to say do commercial flagging jobs 
> first.

Actually, the setting is meant for the opposite because after the 
transcode, commflagging needs to be re-run (new format, new size, new 
frame positions, ... whatever).  However, this is applied on a 
per-recording basis--it's not a general prioritization.  So, you'll 
still get mixed commflag/transcode jobs occurring.

Mike