Re: preempt-rt, NUMA and strange latency traces

From: Sébastien Dugué
Date: Thu Feb 09 2006 - 06:06:50 EST


On Wed, 2006-02-08 at 08:49 -0800, john stultz wrote:
> On Wed, 2006-02-08 at 11:45 +0100, Sébastien Dugué wrote:
> > The more I think about it, the more I tend to believe it's hardware
> > related. It seems as if the CPU just hangs for ~27 ms before
> > resuming processing.
>
> That sounds like to the ~30ms RSA caused SMIs. Does this system have an
> RSA1 or RSA2 card?
>

Hi John,

I think it's an RSA1 card, but no certainty here. I don't think
the x440 came with the RSA2. Is there a way to check for sure without
unplugging everything (It's such a mess of cables behind the box)?

Whats the SMI issue with the RSA? Could the RSA generate bursts of SMI
that could be enough to freeze the CPUs?

When I ran those tests I was logged on the RSA (serial line). I will
try to run the tests again without being connected when I can manage to
get some CPU time (eh! shared machine)...

Thanks.

Sébastien.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/