[mythtv] [mythtv-commits] Ticket #8726: XMLTV grabber selection/navigation broken

[Nick Morrott]

On 9 August 2010 23:10, MythTV <mythtv at cvs.mythtv.org> wrote:
> #8726: XMLTV grabber selection/navigation broken
> -----------------------------------------------------------------+----------
>  Reporter:  Nick Morrott <knowledgejunkie (at) gmail (dot) com>  |           Owner:  ijr
>     Type:  defect                                               |          Status:  new
>  Priority:  minor                                                |       Milestone:  unknown
> Component:  MythTV - Mythtv-setup                                |         Version:  Trunk Head
>  Severity:  medium                                               |      Resolution:
>  Keywords:  xmltv grabber selection navigation tv_find_grabbers  |   Ticket locked:  0
> -----------------------------------------------------------------+----------
>
> Comment (by stuartm):
>
>  Nick, although as you rightly say the 25s timeout isn't related to the
>  issue you are reporting, I'm still tempted to turn the tables and file
>  that as a bug upstream. As I reported to the xmltv-dev mailing list at the
>  time, that check used to take no more than a second, it's not the search
>  which takes so long but the decision to restructure the scripts so that
>  args like --capabilities are handled by the xmltv module. Instead of
>  bailing out early, the entire script and module must be compiled to squirt
>  out a few bytes of hardcoded text.

I'm going to checkout XMLTV 0.5.42 and see how quick it is/was.

>  I'd like to remain behind --capabilities and tv_find_grabbers, but 25s+ is
>  a ridiculously long time to wait for anything to happen in a UI.
>  Especially when that same info could be returned in a couple of hundred
>  ms.

I totally agree that 25s+ is too long to wait for a progress update.
An anonymous ticket was created on the XMLTV tracker earlier to that
effect.

I have a question regarding how mythtv-setup currently handles the
output from a tv_find_grabbers run:

Is it possible to query the buffer that STDOUT from tv_find_grabbers
is redirected into whilst the process is running? Every time a new
grabber is found, its details are sent to STDOUT. If the buffer can be
queried during execution of tv_find_grabbers, the UI could be updated
every second with a count of found grabbers. The relevant bits in
mythtv/libs/libmythtv/videosource.cpp seem to be:

void XMLTVFindGrabbers::run(void)
  ...
  find_grabber_proc.setReadChannel(QProcess::StandardOutput);
  ...

Of course, this fails if the buffer is only readable when
tv_find_grabbers returns or timeouts.


Testing earlier on my everyday X2 3800+ machine (CPU now over 5 years
old) had find_grabbers finish in 10s, finding 24 grabbers. I'm
somewhat amazed 25s isn't long enough!

Cheers,
Nick

-- 
Nick Morrott

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