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Date: Fri, 2 Jan 2004 10:00:16 -0800 (PST)
From: Tom <tom@sdf.com>
To: Oliver Brandmueller <ob@e-Gitt.NET>
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cc: freebsd-current@freebsd.org
Subject: Re: Hot Swapping CPUs?
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On Fri, 2 Jan 2004, Oliver Brandmueller wrote:

> Hi all,
>
> With late ULE you can watch a process hopping between CPUs. This seems

  You can see that with the 4BSD scheduler too.  It has always been a
"feature" on the scheduler.  I can see this on FreeBSD 3.5 too.

> to the base functionality for CPU hot swapping. One would need (apart
> from a Motherboard that's able to that ;-)) some control over CPUs now,
> like disabling a physical CPU during runtime (which could also be done
> automatically on certain filure onditions).

  sysctl already exposes some variabled to control CPUs on an SMP system.

  It is a pretty hard to detect a CPU failure in software, because the
software detection will fail at the same time the CPU does.

> Is there any work in progress in this direction? Would be a very neat
> feature for high availability systems.
>
> - Oliver


Tom