[mythtv-users] mythfrontend timeout when tuning HVR-950Q

[Bob Cunningham]

On 10/28/2009 09:02 PM, Devin Heitmueller wrote:
> On Wed, Oct 28, 2009 at 9:49 PM, Bob Cunningham<FlyMyPG at gmail.com>  wrote:
>> On 10/28/2009 04:03 PM, Bob Cunningham wrote:
>>>
>>> I just finished a fresh install of 0.22 RC1 from
>>> rpmfusion-updates-testing on Fedora 11.
>>>
>>> Everything went well from the start:
>>> - Configuration OK (including XMLTV load for QAM SD, and channel scan
>>> for QAM HD)
>>> - mythfilldatabase OK
>>> - MythMusic OK
>>> - MythWeb OK (still need to clean up channel mapping and tweak other
>>> settings)
>>>
>>> But I can't watch LiveTV! My HVR-950Q works fine with tvtime (SD) and
>>> xine (HD).
>>>
>>> Neither the frontend nor the backend are crashing. Google searches yield
>>> no help.
>>>
>>> The output from mythfrontend is:
>>>
>>> 2009-10-27 16:40:12.573 TV: Attempting to change from None to Watching
>>> WatchingLiveTV
>>> 2009-10-27 16:40:12.578 MythContext: Connecting to backend server:
>>> 127.0.0.1:6543 (try 1 of 1)
>>> 2009-10-27 16:40:12.579 Using protocol version 50
>>> 2009-10-27 16:40:12.582 Spawning LiveTV Recorder -- begin
>>> 2009-10-27 16:40:19.586 MythSocket(887ddd8:40): readStringList: Error,
>>> timed out after 7000 ms.
>>> 2009-10-27 16:40:19.587 RemoteEncoder::SendReceiveStringList(): No
>>> response.
>>> 2009-10-27 16:40:19.587 Spawning LiveTV Recorder -- end
>>> 2009-10-27 16:40:19.587 GetEntryAt(-1) failed.
>>> 2009-10-27 16:40:19.589 EntryToProgram(0 at Wed Dec 31 16:00:00 1969)
>>> failed to get pginfo
>>> 2009-10-27 16:40:19.589 TV Error: HandleStateChange(): LiveTV not
>>> successfully started
>>> 2009-10-27 16:40:19.589 We have a RingBuffer
>>> 2009-10-27 16:40:19.639 TV Error: LiveTV not successfully started
>>>
>>> /var/log/mythtv/mythbackend.log contains no errors or warnings.
>>>
>>> Since I'm using an HVR-950Q, and since the HD channel scan worked fine,
>>> my guess is the problem may be the slow firmware load, which takes about
>>> 8 seconds, but it seems mythfrontend times out in 7 seconds.
>>>
>>> The driver seems to reload the firmware at every possible opportunity,
>>> independent of the hardware state, each time either the SD or HD device
>>> is opened, such as when changing from an SD channel on /dev/video0 to an
>>> HD channel on /dev/dvb/adapter0. So this delay will happen a lot.
>>>
>>> Any way to have the frontend be a bit more patient?
>>
>> This is due to the value of kShortTimeout being hard-coded to 7000 in
>> mythsocket.cpp.
>>
>> Can this be changed to a configurable setting?  Perhaps the tuner
>> configuration in mythsetup should have a checkbox for "Slow Tuner" that the
>> frontend could read for LiveTV, that would cause the timeout to double.
>>
>> If it has to stay as a constant, it should be set higher.
>>
>> Should I open a bug on this?
>>
>>> Or can I tell the driver to ease up on the firmware reloads?
>>
>> If nobody here has any suggestions, I'll ask on the linux-media list.
>
> Hi Bob,
>
> Sorry I've been tied up in development and not watching email for the
> last couple of hours.  I answered your email over on linux-media
> before I got around to looking at my mythtv-users folder.
>
> I *am* glad to see thought that you actually tracked down where the
> timeout is coming from.  I hadn't yet had a chance to chase down where
> in the MythTV source the timeout was actually occurring.  It would be
> great to see this made configurable, since it's easier for users to
> reconfigure a MythTV setting than a modprobe option.  Alternatively, I
> might want to float past the MythTV devs the idea of making the
> timeout 10 seconds instead of 7, which would result in the 950q
> working without the user needing to do anything (and in reality,
> people shouldn't be hitting the timeout anyway, so there shouldn't be
> a huge complaint about the difference between ten seconds and seven).
>
> Devin

A work-around has been found: See the linux-media thread "HVR-950Q problem under MythTV" for details.  The limitation of this fix is that my tuner is now an insomniac.

The generic issue with MythTV is still unresolved: Timeouts related to tuners and other hardware should be settings, not constants.

-BobC