[mythtv-users] Mythtv .19 live watching

[Brian Wood]

On Jul 13, 2006, at 2:45 PM, Isaac Richards wrote:

> On Thursday 13 July 2006 2:25 pm, chris at cpr.homelinux.net wrote:
>> The kids walking away or the dog stepping on the keyboard are only
>> problems because the design assumptions make them into problems.  I
>> get your point -- "stuff happens" -- but a robust application
>> shouldn't even see most of that "stuff" as problems.
>
> Please explain how to do live-tv in a full-disk situation (before  
> starting
> live tv) without:
> a) deleting a recording the user has already said can be deleted.
> or
> b) reserving space for live-tv only (and so preventing less to be  
> recorded in
> the first place, irregardless of how often someone uses live-tv).
> or
> c) just disallowing live-tv to run, even though there are programs  
> that could
> be deleted, and the user obviously wants to go into live-tv.
>
> Obviously, c will have to happen anyway, if there's nothing marked as
> deletable, but it's nice to keep that from happening if at all  
> possible.  I
> rather dislike b, because I want as much recorded at any given time  
> as I have
> space for.
>
> Even with a ring-buffer (ie, <= 0.18), you need to have space on  
> the drive
> available to start it in the first place.
>
> The problem with chunking livetv into smaller boundaries than a  
> full program
> is that in the full disk situation (which should be the norm for  
> most people
> after a short time of recording things), there won't be _any_  
> chunks other
> than the most current one being recorded.  Everything else will  
> have been
> auto-expired to make space for the next chunk.  To me, that makes  
> the ability
> to keep the recording completely useless.  What use would a 5 minute
> ring-buffer be?  The minimum I'd consider chunking a live-tv  
> program to would
> be 8 hours, I think.  Harddrives are cheap enough for that, anyway.
>
> Let's see, other options..  could prompt the user so that they're  
> explicitly
> aware that something's going to be auto-expired when they enter  
> live-tv, but
> the normal user that uses auto-expire (who always a full-drive) is  
> going to
> get that message _every_ _single_ _time_ they start live-tv.   
> That's not
> helpful or useful, that's annoying.  A user that deletes programs  
> manually
> wouldn't ever see the prompt, but they'd almost never be in the  
> situation
> where live-tv would possibly need extra space in the first place.
>
> Way I see it: if you don't want something to be autoexpired, don't  
> turn it on
> in the first place.  If a program is allowed to be autoexpired,  
> it's _going_
> to be deleted at some point.  If you don't want something deleted  
> when space
> is needed, simply disable autoexpire for it.  I don't see that as a  
> design
> flaw.
>
> I just got a 'global live-tv inactivity timeout' proposed to me,  
> which could
> help.  Ie, automatically exit after 4 hours of inactivity or whatnot.
>
> Any other ideas?  Please, just don't ignore what happens when the  
> disk is
> _always_ full, and remember that regular scheduled recordings are  
> also going
> to be causing auto-expireable programs to be deleted.
>
> And no, automatically buying and installing new harddrives won't  
> work. =)
>


It's simple math: If you record video at a faster rate than you  
delete it you are going to run out of space and not be able to do  
something that you want to do. That might by LiveTV or recordings.

I try and make my record and delete rates equal, as that is the only  
way you are going to have a happy system, your hard drive space is  
really only a buffer to hold things temporarily.

I either watch the material and then delete it, or burn it to DVD and  
then delete it if I want to save it but don't expect to watch it in  
the near future.

I have also found the myth_archive_job.pl script to be helpful for  
moving recordings to a USB drive if I need additional space temporarily.

But the problem is identical to body weight control, if you take in  
more calories than you burn you will get heavier, and no tablet or  
hypnosis or positive thinking can change that.

And no amount of re-coding or design philosophy changes will make the  
slightest difference in the end either :-)