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From: John Baldwin <jhb@FreeBSD.org>
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Date: Fri, 4 Jun 2004 14:50:24 -0400
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cc: Roman Kurakin <rik@cronyx.ru>
Subject: Re: FreeBSD support in SMP platform
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On Friday 04 June 2004 01:06 pm, Roman Kurakin wrote:
> John Baldwin wrote:
> >[...]
> >FreeBSD will see and support up to 16 CPUs, but it won't be very stable on
> >probably more than 4 or 6.
>
> What is the reason?

When a thread is made runnable the idle CPUs contest on sched_lock so much 
that invariable one CPU ends up timing out on sched_lock and panic'ing.  This 
will be fixed eventually but not in the near future.

-- 
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org