[LAU] rtirq - what does it improve, and how can I measure it?

[Ralf Mardorf]

On Mon, 2012-05-07 at 14:54 +0200, Robin Gareus wrote:
> With linux >= 3.0 and the preemt-RT patch, you don't need the
> 'threadirq' option with CONFIG_FORCE_THREADIRQ=y:
> 
> http://anonscm.debian.org/viewvc/kernel/dists/trunk/linux-2.6/debian/patches/features/all/rt/genirq-force-threading.patch?revision=18299&view=markup

So when I build a kernel-rt ex 3.0 from kernel.org source I need to use
boot option threadirqs, if it isn't patched?

On AV Linux I run the 3.0.23-avl-7-pae with and the self-build
3.0.23-rt40 without threadirqs. This way there's no difference between
those kernels. I can't make music using JACK1 (didn't test JACK2 until
now with AV Linux).

But at least kernel-rt < 2.6.39 are ok without threadirqs ;)?

But CONFIG_IRQ_FORCED_THREADING has to be set for a kernel-rt too?
spinymouse at precise:~$ grep FORCE /media/avlinux/boot/config-3.0.23-rt40
CONFIG_IRQ_FORCED_THREADING=y

Regards,
Ralf