[PlanetCCRMA] CCRMA SMP FC4 crashes

Fernando Lopez-Lezcano nando@ccrma.Stanford.EDU
Mon Dec 5 16:57:02 2005


On Mon, 2005-12-05 at 14:20 -0500, Roman Katzer wrote:
> Fernando,
> 
> thanks for your quick response!
> 
> For the record, I'm extremely thankful for your dedication to CCRMA
> and your help to everybody on this list.  Kudos!
> 
> On 05/12/05, Fernando Lopez-Lezcano <nando@ccrma.stanford.edu> wrote:
> > > Any ideas as to what could be causing this?
> > A bug in the realtime preemption patch that manifests on your hardware.
> 
> Do I really need this patch by the way? Would it be sufficient to run
> the stock (yum-installed) kernel with CCRMA utilities?

Sure, it should work. It depends on how concerned you are with low
latency. Fedora Core's kernel (specially the latest versions) should
work fine with the rest of Planet CCRMA. 

> > You could try a more recent kernel that I never officially released but
> > many people are successfully using.
> 
> Just installed it, so I'll wait and see whether it's stable.
> 
> Two quirks:
> apt-get update comes back saying
> -----------------------------------------------------------
> W: There are multiple versions of "kernel-smp-devel" in your system.
> 
> This package won't be cleanly updated, unless you leave
> only one version. To leave multiple versions installed,
> you may remove that warning by setting the following
> option in your configuration file:
> 
> RPM::Allow-Duplicated { "^kernel-smp-devel$"; };
> 
> To disable these warnings completely set:
> 
> RPM::Allow-Duplicated-Warning "false";
> W: You may want to run apt-get update to correct these problems
> -----------------------------------------------------------

Oh, you need to add something to /etc/apt/apt.conf now that
kernel-*devel can be a multiply installed package, change this line:

	"^kernel(-(BOOT|.*devel|smp|bigmem|debug|doc|source.*)|)$"; 

> when I run apt-get update again, no warning message. After an apt-get
> upgrade, the next apt-get update will give the same message.
> I hope to have remedied it now by rpm -e'ing the 2.6.11 and 2.6.14
> versions of kernel-smp-devel.

That's cool. 

> Quirk (or phenomenon) number two:
> even doing nothing at all, top shows a load of greater than 1, often
> greater than 2.

I have seen this, never found out what's going on and ignored it :-)

> This never occurred on the FC1 machines I tend to. I can't say whether
> this happens with a stock kernel.
> 
> Extra credit question:
> will CCRMA support yum at some point?

It already does, I don't document it in the main pages as I have don't
use it myself and have not had time to add documentation about it...

-- Fernando