[mythtv-users] Are there any throttling features in Mythtv?

[Brad DerManouelian]

On Feb 3, 2009, at 8:01 AM, Mike Perkins wrote:

> Sunday evening, we sat down to watch a film I'd recorded just before  
> Christmas, 2 hours long. This was about 7:45 pm. An hour and a half  
> later, the whole system hung. There was not the slightest sign that  
> anything was wrong up to the point it froze.
>
> After some investigation of the front end[1] I discovered that the  
> back end had hung. This was because at 8:55 pm the back end had  
> begun three simultaneous recordings on three DVB-T tuners.  
> Apparently my back end couldn't cope with reading and writing four  
> streams simultaneously[2].
>
> Now, before you all scream "throw more hardware at it!" I would like  
> to point out that whatever system you've got, a point will come when  
> you are likely to stress it. So it occurred to me to wonder if there  
> was any kind of throttling or warning available in mythtv, apart  
> from "max # of jobs to run on this backend".
>
> For example, if I were to play a long film that happened to overlap  
> a period of heavy recording, would it be possible for the system to  
> say something like "this probably isn't a good idea, go and watch  
> something shorter"? Or for it to show me what's likely to happen  
> within the playing time of the selected program?
>
> I wouldn't want to go as far as rescheduling, but some kind of  
> information screen might be useful. At the moment, to find out  
> what's scheduled involves going into "schedule programs" then  
> "upcoming recordings" to see a list, then backing out and going to  
> "watch recordings" to find something to watch. Anyone any suggestions?
>
> [1] see separate post. The front end was ok in this instance.
> [2] recording three simultaneous streams is known to work ok.  
> Recording 2 streams and watching one is known to work ok.

When I add tuners, I always set them all to record to make sure my  
system can handle it. It's possible for me to record 8 things at the  
same time. My system doesn't fall down when it happens (never happened  
naturally, only when I forced it to happen). How is mythtv supposed to  
know that your system can't handle 3, but mine can handle 8 and at  
what point will my system not be able to handle any more? I haven't  
found my limit.

-Brad