[mythtv-users] setting MythTV to wake up at the right time

David Watkins watkinshome at gmail.com
Wed Jan 24 22:41:00 UTC 2007

On 24/01/07, Yves de Brauer <ydebx2 at free.fr> wrote:
> I have a problem I would like to solve.
> I use nvram-wakeup to wake up the backend for recording. But some time
> the beginning of a show is missing.
> After some search, I discovered that it is like MythTV do not take into
> account the "start early" I put in the recording rules to wake up the
> computer at the right time.
> For example, I set the backend to wake up 2 minutes before a recording
> as it takes about 1 minute to be on.
> If a TV show is forecast at 01:10, MythTV set the backend to wake up at
> 01:08, OK.
> Now if I put a start early of 5 minutes because that channel is not very
> reliable, I expect the backend to wake at 01:03 and start recording at
> 01:05. Unfortunately It awakes at 01:08 as before and starts recording
> at about 01:09 when it is on.
> Note: When I stop the Backend with the mythwelcome command "Shutdown
> Now" It set the right time to wake up I.e. 01:03.....
> What is the correct setting? Is it a bug?  Please help.

from the nvram-wakeup README file

NOTICE  that you do not specify the time to be set in nvram but the
       time  at which  the machine  should be  up  and  running.  I.e.
       nvram-wakeup will  set the  wakeup time  WAKEUP_BEFORE  minutes
       before the time specified with the --settime option.

I believe that the default WAKEUP_BEFORE value is 10 minutes.
Certainly if I run nvram-wakeup with a value of 13:00 and shutdown,
then my machine wakes up at 12:50.  In plenty of time for the

Not sure why this isn't working for you!

It is possible that the scheduler does not take account of 'start
early' settings when configuring  nvram-wakeup.  I've seen something

When I schedule sports events I often schedule them to start late to
avoid the long introduction before the event starts.  I have noticed
that in this case the backend wakes up at the programme start time
rather than just before the recording starts.  Maybe you are seeing
the same thing?  (Although you say you saw the correct value in the
shutdown script which implies not).

If I were you I'd test your nvram-wakeup by running it manually to see
what it does.  Then test mythtv by looking at the mythbackend log
during a shutdown to see what it's asking nvram-wakeup to do.

Hope this helps.


More information about the mythtv-users mailing list