[linux-audio-user] Re: [linux-audio-dev] [ANN] E-Radium V0.61b

[Lee Revell]

On Wed, 2005-07-13 at 01:03 +0200, Florian Schmidt wrote:
> Some semieducated blabbering ahead (might be all wrong):
> 
> I think i once read that interrupt handling "short circuits" the linux
> scheduler (in the sense that not only at every timer interrupt but also
> at the end of finishing any interrupt handler the kernel looks which
> processes are ready to run etc. and maybe there's a high prio process
> waiting just for that interrupt (by i.e. polling or reading on a device
> file). 
> 
> So for all those realtime processes that depend on events that are
> triggering interrupts (like soundcards' irqs) the timer interrupt really
> doesn't matter. I'm not sure at all though this applies to midi handling
> (and especially to alsa_seq when routing from one app to another) or is
> even correct in any sense at all :)
> 
> Anyone can shed light? 
> 

Correct, it's not an issue for apps driven by hardware interrupts like
JACK, because the sound card consumes data at a constant rate.  But for
MIDI or video where you have to periodically push data to the device it
matters.

Lee