[mythtv-users] Recording Priority = 99 not a trump all?

[Douglas Peale]

On 06/23/2010 03:24 PM, Michael T. Dean wrote:
> On 06/23/2010 06:05 PM, Jason Ward wrote:
>> On 23 June 2010 22:55, Douglas Peale wrote:
>>   
>>> On 06/23/2010 02:33 PM, David Engel wrote:
>>>     
>>>> When SchedMoveHigher is enabled, the
>>>> scheduler moves recordings around one at a time and the first fit
>>>> wins.  it does not continue on looking for "better" fits.
>>>>        
>>> The example I cite is a recording of NCIS on ION. I have 7 copies of
>>> ION on
>>> my system 1 OTA HD, 3 cable HD, and 3 cable SD. All
>>> three cable SD channels had a priority of -10 the rest were priority 0.
>>> There was nothing else scheduled at that time that would
>>> match any of my recording criteria. No conflicts.
>>>
>>> So, you contend that in this situation for the scheduler to choose a SD
>>> channel over an HD channel is not a bug?
>>>      
>> Well David says the scheduler is written to find the first fit not the
>> best
>> fit,
> 
> Well, more precisely, David said that when users have the setting I
> mentioned way back in the 3rd post in this thread (
> http://www.gossamer-threads.com/lists/mythtv/users/441014#441014 )
> enabled, one of its effects is to disable best-fit scheduling and,
> instead, use first-fit scheduling in some circumstances.
> 
> In other words, the setting he meant by, "SchedMoveHigher," is actually,
> "Reschedule higher priorities."
> 
>>   so yes, there is no bug in so much as the scheduler has worked as it is
>> designed to work.
> 
> Exactly.  And, more importantly, as the user configured it to work.
> 
>>    However, I would agree this isn't exactly desirable
>> behavior,
> 
> Which is why we have a setting that you can disable (in mythfrontend
> settings, Utilities/Setup|Setup|TV Settings|Recording Priorities,
> IIRC).  The default is that "Reschedule higher priorities" is enabled
> because we got far more users complaining that MythTV wasn't recording
> everything they wanted than users complaining that they don't get a show
> they want until its second airing.
> 
> Again, this is all explained very nicely in
> http://www.mythtv.org/docs/mythtv-HOWTO-12.html .  Note, also--as I've
> said /way/ too many times--anyone who modifies /any/ priority other than
> recording rule priorities should read and understand that entire section
> before doing so.  (And, after reading it, you'll likely see that you
> don't want to modify other priorities.)
> 
> Mike


If I read those correctly, once the scheduler has decided that show X (say "NCIS") has the highest priority and should be
scheduled next, it arbitrarily and randomly chooses a channel & tuner from those not currently scheduled for something else that
is capable of receiving the particular show, completely ignoring channel priority and tuner priority.

So there is no way to reliably tell the scheduler that channel Y is flakey and should only be used as a last resort, and channel
Z is always a better choice for the same show than channel W.

Ouch! This makes life difficult for those of us with mixed tuners & mixed sources. I personally have two antennas aimed in
different directions, and limited basic cable. I also have two different types of tuner in my system. The best tuner for a
particular show depends on the channel due to variances in compression, signal path, & source. I have two sources each for NBC &
FOX (different cities). It would be nice if the tuner priority and channel priority could be used to get MythTV to prefer the
best choice in every situation. As it is, I must either suffer random source selection, or disable lower quality channels and
have a higher probability of missed recordings due to conflicts.