[mythtv-users] slow dvb lock in .21 (+some timing data)

[David Lister]

Greg Estabrooks wrote:
>> I'd really like to know about the change you mentioned. I would try it
>> right away -- all my sources are up-to-date, all 4 cores ready to roll
>> and I'm in the mood for hacking. :) Let me know what to try and if I get
> 
>  Just for sh*ts and giggles comment out the calls to Initcc608 and InitCC708 in the InitDefaults() function inside of libs/libmythtv/osd.cpp
> 
>  If you require CC then don't do it since it will be very crashy without those.
> 
>  This made a huge speed up on SOME systems with SOME configurations. No guarantees for you or even most others.

It's the same. Timeline of channel change: releasing OK button -> till
complete "LOCK" -> till the first picture of the new channel appears.
Times are in seconds:

Within one multiplex:

 push | lock | change
>-----+------+-------->
 0    | 2.97 | 6.75
 0    | 2.79 | 6.56
 0    | 2.92 | 7.11

Different multiplex:

 push | lock | change
>-----+------+-------->
 0    | 4.50 | 7.74
 0    | 3.69 | 6.92
 0    | 4.00 | 7.24

Different sat (DiSEqC switch):

 push | lock | change
>-----+------+-------->
 0    | 4.95 | 8.56
 0    | 6.16 | 9.85
 0    | 5.31 | 9.18

Plain dumb channel lock using szap takes the same about of time
(including DiSEqC switch):

$ time szap-s2 -x -a2 -n15 -r -c ~/channels.conf
real	0m0.662s

This is the best I can do. I guess it's even faster than my previous
HTPC (also FE+BE) and HVR-500. My DVB cards are TeVii S640. Everybody
has to agree these times are not ideal. They are bearable, tolerable,
but nothing to be proud of.

Regards,
Dave