[ardour-users] low latency kernel problems

[philicorda]

On Wed, 2006-05-17 at 17:57 -0700, Mark Knecht wrote:
> On 5/17/06, philicorda <philicorda at ntlworld.com> wrote:
> > On Wed, 2006-05-17 at 12:19 -0700, Mark Knecht wrote:
> <snip>
> > >
> > > On my single core AMD64 the 2.6.15-rt kernels boot, as do the
> > > 2.6.16-gentoo kernels. Using the new Gentoo pro-audio overlay I tried
> > > building 2.6.16-rt22 yesterday. I hangs early in the boot when it's
> > > installing the IO Schedulers.
> >
> > I have 2.6.16-rt22 working fine on my AthlonXP. (Gentoo Gcc 4.1.0)
> > The only IO scheduler compiled in is 'deadline'.
> >
> > #
> > # IO Schedulers
> > #
> > CONFIG_IOSCHED_NOOP=y
> > # CONFIG_IOSCHED_AS is not set
> > CONFIG_IOSCHED_DEADLINE=y
> > # CONFIG_IOSCHED_CFQ is not set
> > # CONFIG_DEFAULT_AS is not set
> > CONFIG_DEFAULT_DEADLINE=y
> > # CONFIG_DEFAULT_CFQ is not set
> > # CONFIG_DEFAULT_NOOP is not set
> > CONFIG_DEFAULT_IOSCHED="deadline"
> >
> >
> > The Gentoo pro-audio overlay is a fine thing isn't it?
> > Respect is due to those who put it together.
> >
> 
> Hi,
>    Thanks for the heads-up. Unfortunately it didn't work for me. As
> expected I now only see the noop and deadline schedulers registered
> and then the machine hangs. Rebooting into 2.6.16-gentoo-r2 works
> fine, as does the older 2.6.15-rt18.

Ah, that's the limit of my expertise then. :)
I can send you the .config if you like.

Though I don't really change anything in menuconfig other than disabling
'optimise for size' and 'Configure standard kernel features (for small
systems)' and turning on the security model for users rt.

> 
>    The pro-audio overlay is a great but I'm not sure I'm working it
> perfectly well. For instance,
> 
> eix rt-sources
> 
> tells me there isn't a kernel but
> 
> emerge rt-sources
> 
> says it's in the pro-audio overlay, downloads and correctly installs it.
> 
> lightning ~ # eix rt-sources
> 
> Found 0 matches

I didn't know about eix. Neat. 
It does not seem to find any of the layman ebuilds at all on my
computer. It appears someone has submitted this as a bug in the gentoo
bugzilla.

http://bugs.gentoo.org/show_bug.cgi?id=132874

> lightning ~ # emerge -pv rt-sources
> 
> These are the packages that I would merge, in order:
> 
> Calculating dependencies ...done!
> [ebuild   R   ] sys-kernel/rt-sources-2.6.16-r22  -build -doc -symlink 0 kB [2]
> 
> Total size of downloads: 0 kB
> Portage overlays:
>  [1] /usr/local/portage
>  [2] /usr/portage/local/layman/pro-audio
> lightning ~ #
> 
> I'm now confused about using this. I used the layman method of installing it.
> 
> Thanks,
> Mark