[linux-audio-dev] Audio/Midi system - RT prios..

[Lee Revell]

On Fri, 2005-12-30 at 19:01 +0100, Werner Schweer wrote:
> higher priority thread can interrupt lower priority threads. What do
> you gain if the soundcard can interrupt the jack thread? I believe
> it does not matter. 
> Interrupt routines on a well behaved system are using only some
> microseconds so it should not matter at all for audio purposes.
> Or do i miss something here? 

I think you are right.  It's not the relative priority of IRQ threads
that matter (most IRQs run for far less than 1ms anyway and the
soundcard IRQ thread and JACK should never contend) but the
preemptibility of softirqs (and a few rude hardirqs like IDE) that makes
the biggest difference.  Long running softirqs can delay preemption by
~10ms with 2.6.14 OOTB.

Lee