Subject: Re: preempt-rt, NUMA and strange latency traces
From: Lee Revell <rlrevell@joe-job.com>
To: =?ISO-8859-1?Q?S=E9bastien_Dugu=E9?= <sebastien.dugue@bull.net>
Cc: john stultz <johnstul@us.ibm.com>, Steven Rostedt <rostedt@goodmis.org>,
       "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       Ingo Molnar <mingo@elte.hu>
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Date: Fri, 10 Feb 2006 14:07:54 -0500
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On Fri, 2006-02-10 at 14:07 +0100, S?bastien Dugu? wrote:
> That's the problem and I'll have to synchronize for a proper window
> for running my tests.
> 
>   Is this SMI thing IBM's eyes only stuff or is it documented
> somewhere?
> 

No, I wish it was just IBM.  Lots of modern systems unfortunately use
SMM (system management mode, which is entered when we get a system
management interrupts) to implement all kinds of PM and BIOS junk and
various value added features.

Most of these systems are laptops and are utterly unusable for low
latency work.  Worse, most of this stuff is considered highly
proprietary by the vendors (probably because it leands to such suckage).

Lee

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