On Mon, Oct 28, 2013 at 11:05 AM, Gene Heskett <gheskett@wdtv.com> wrote:

I have not yet looked at SteamOS, but you are claiming realtime for it.
That pulls my curiosity trigger because one of my hobbies is CNC
machinery, and its realtime demands are far more stringent than some .1
millisecond accurate audio delivery. Currently we are running linuxcnc on
2.6.32-122-RTAI, but that RTAI patch is invasive as hell, [ ... ]

If SteamOS is claiming real time, just how "realtime" is it?

There is no comparing even the RT kernel with RTAI. They are totally different conceptions. RTAI is basically a microkernel that runs a normal kernel as a client. It requires drivers for every device that is included in "realtime land" (i.e. for audio, you cannot use ALSA, you would need new drivers that run in the RT executive.

SteamOS *might* use the RT kernel, but I'd be incredibly surprised if they even considered RTAI.

--p

(disclaimer: i haven't looked at RTAI for quite a long time, things might have changed)