[mythtv-users] Mythtv .19 live watching

[Osma Ahvenlampi]

On to, 2006-07-13 at 16:45 -0400, Isaac Richards wrote:
> 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.

I'd think that would be fairly obvious, if you consider not the current
implementation, but what a user would expect to happen with a TV set:

d) display live tv, but show a message over the OSD that storage space
is not available, so time-shift capability and recording are disabled.

If you'd want to make it fancy, provide a shortcut for the user to
delete one of two or three shows the system expects to be least wanted
without having to exit live tv. The decision on what is least wanted
should be what the auto-prioritization would have deleted if there were
expirable programs.

> 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?

And that's entirely reasonable. If there is no space available, the user
can not expect to keep a recording. She will expect to be able to watch
tv without recording, since she could do that without MythTV 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.

To me, auto-expire is the natural default setting, as it is the only way
the system can keep space available without forcing manual management.
In fact, I think it should always be enabled by default, and the "Don't
auto expire this show" should in fact be an "Archive this show"
function, perhaps tied to DVD-R storage.

This is because the first choice should always be something that a)
provides value to the user and b) requires as little or less management
than the previous alternative (ie, minimizes cost for the provided
value).

MythTV provides both of these to the degree that: it makes time-shifting
possible, whereas without a DVR it is not, and it makes recording easy,
thanks to automatic program guide and episode searching. But if you turn
off auto-expire, you break at least one of those guidelines.

-- 
Osma Ahvenlampi   <oa at iki.fi>    http://www.fishpool.org