[mythtv-users] Re: Regular Overnight Lockups

[Jarod C. Wilson]

On Tuesday, Jun 17, 2003, Steven J. Finnegan wrote:

> Every morning I find the myth system locked up (frozen picture, no 
> sound). This requires shutting down the backend and frontend and 
> restarting them (the Linux system is still running).
>
> Since this happens every night, I decided to see what cron.daily 
> functions were occurring. This is what I discovered... (RH9)
>
> makewhatis.cron - Causes audio errors (broken audio). After it 
> completes, the frontend log fills with a bunch of "Audio buffer 
> overflow, audio data lost!" messages, and audio is static. Changing 
> channels recovers the audio. (Using ALSA)
>
> But the real culprit is slocate.cron. This causes myth to lock up 
> every time its run, with the message "Backend stuffed up in 
> RequestRingBufferBlock". Slocate causes the locate database to be 
> rebuilt, which creates a great deal of disk activity.
>
> slocate.cron contains the following lines...
>
> #!/bin/sh
> renice +19 -p $$ >/dev/null 2>&1
> /usr/bin/updatedb -f "nfs,smbfs,ncpfs,proc,devpts" -e 
> "/tmp,/var/tmp,/usr/tmp,/afs,/net"
>
>
> Anybody else seeing this problem? Any suggested remedies (other than 
> avoiding updating the locate db)?

It sounds like you leave your system tuned in to a channel, constantly 
capturing and playing back video... All the hard disk activity that 
generates, run concurrently with updatedb, appears to be more than your 
system can handle. I believe the easy fix would be to stop playback. 
Exit from viewing, and leave your system at the MythTV screen instead. 
Leaving it capturing and playing back all the time is murder on your 
hard drive... With that off, your system ought to not lock up, but that 
does present an issue if you happen to be watching TV around 4am when 
cron.daily kicks into gear... :)

-jcw