[mythtv-users] Folding at home, having it start/stop between recordings/jobs??

[Yan Seiner]

On Tue, April 21, 2009 1:28 pm, Bobby Gill wrote:
>>
>>
>> man nice
>> man renice
>>
>> Basically set the priority to the lowest:
>>
>> IIRC something like
>>
>> renice 20 f at h
>>
>> should do the trick.  I do the same thing; I have a huge ffmpeg job that
>> runs for about 10 minutes, hammering the drives and the CPU.  It caused
>> all sorts of problems with myth until I re-niced it to the lowest level
>> possible.
>>
>> --Yan
>>
>
> Thanks Yan. So for my intermediate self, what is that doing? I don't have
> any man pages for nice/renice. I just googled and see that it is
> rescheduling the process priority, but would that completely stop the f at h
> if
> a recording starts, and then when the flagging is done after, f at h starts
> again? Or is that as simple as it sounds: giving the mythbackend the top
> dog
> priority when it starts recording/a job and sending f at h way down in cpu
> usage?
>

The latter.  Basically, a process with a higher priority will get
resources before a process with a lower priority. (It's a bit more
complicated and I don't pretend to understand it but for country bumpkins
like me that explanation will suffice.)

So f at h is grinding along, sucking up 100% CPU, and then myth cranks up,
needs CPU cycles, and the f at h process will get less CPU.  Lots less if
myth is high in the list and f at h is low.

I'm surprised you don't have man pages on those; AFAIK they're a basic
part of any *nix.  Your distro must have them as an optional install.

-- 
Yan Seiner, PE

Support my bid for the 4J School Board
http://www.seiner.com