Re: [linux-audio-user] Re: Frustrated bigtime

On Tue, 23 Aug 2005 11:05:57 +1000
"Shayne O'Connor" <forums@email-addr-hidden> wrote:

> Noah Roberts wrote:
> > On 8/22/05, tim hall <tech@email-addr-hidden> wrote:
> >
> >>More unsubstantiated comment, for which I apologise:
> >>
> >>On Monday 22 August 2005 06:54, Lee Revell wrote:
> >>
> >>>Try the latest RT preempt patch that works with 2.6.12. Or, why not
> >>>just use a prepackaged RT patched kernel like the Demudi one?
> >>
> >>I would guess that Noah has already tried it. There is enough
> >>traffic on the AGNULA-users list to suggest that none of the
> >>prepackaged DeMuDi 2.6 RT kernels are actually stable, they seem to
> >>work perfectly on some hardware and not on others (partic. low-spec
> >>and 64bit machines).
> >
> >
> > The 2.6.13 idea was probably the most helpful. Applying the rt
> > patch was an idea given by Revel, though not for .13...but thanks
> > for yelling at me about it anyway. .13 comes with the RT patch
> > applied already so it isn't necissary to apply any patch to this
> > kernel....not that I don't know how.
>
> have i missed something? i've been applying patches to the 2.6.13
> kernel:
>
> > http://people.redhat.com/mingo/realtime-preempt/patch-2.6.13-rc6-rt12
>
> is this not required anymore (makes me wonder what i actually did
> when patching that kernel then ...) ?
>
> shayne
>

Full realtime preemption is not yet in mainline. They just merged:
( ) No Forced Preemption (Server)
( ) Voluntary Kernel Preemption (Desktop)
( ) Preemptible Kernel (Low-Latency Desktop)

So for a full preemptible DAW kernel you'll still need ingo's patch
applied.
btw i had the same experience with 2.6.12 and RT... horrible stability,
not faster in any way as vanilla+normal preemption. The best so far is
2.6.11.x + rt, 2.6.13-rc6 is quite stable here, but i use it w/o RT and
am back on Con Kolivas -ck2 with new improved SCHED_ISO and very pleased
with it so far. But for a production DAW i would use 2.6.11.x + ingo's
RT.

Regards
Tom