[mythtv] [bug] mythweb update pre/post rolls?

Bruce Markey bjm at lvcm.com
Wed Apr 7 22:20:04 EDT 2004


Chris Pinkham wrote:
>>The first show would stop recording at :59:00. The console
>>would report "backend still changing state, waiting.." and
>>for the next 17 seconds, the slave backend would send about
>>3600 INSERT statements to the database. One per keyframe. After
>>all have been sent over the net, the console reports, "changing
>>state finished, starting now" and about two seconds later,
>>presto, new recording starts 19 seconds late. This delay is
>>not caused by the scheduler run which we know runs in a few
>>hundredths of a second or anything about time fields in the
>>'record' table.

> I should be able to fix this so that it only writes out only the new
> entries in NuppelVideoRecorder::WriteSeekTable() like it does in
> NuppelVideoRecorder::UpdateSeekTable().  I didn't notice this
> slowdown when I wrote the code to save the positionmap to the DB.

Great, thanks. I knew that it was re-writing the positionmap even
after it had been writing out every 15 sec throughout the recording.
Seems like good measure. It wasn't until I went poking around after
David and Matt were looking into the delay in terms of the scheduler
run. Today I was looking at the possibility of doing one SELECT
then comparing for differences (should be none =). The select results
would still be fairly large but should only take a fraction of the
time.

> Now that my DB is on a slower machine and remote from the master
> backend I notice the slowdown more.
> 
> Added to my TODO list.

I'll leave this to you then. Thanks,

--  bjm


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