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Date: Sun, 27 Apr 1997 23:49:50 -0400 (EDT)
From: Ben Black <black@zen.cypher.net>
To: Chuck Robey <chuckr@mat.net>
cc: FreeBSD-SMP@FreeBSD.org
Subject: Re: SMP
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On Sun, 27 Apr 1997, Chuck Robey wrote:

> On Sun, 27 Apr 1997, Ben Black wrote:
> 
> > freebsd-smp is not the best example of how to do SMP.  it uses the 
> > simplest method: one giant kernel lock.  i don't know that it is 
> > particularly representative of advanced SMP operating systems (though 
> > linux also uses a giant kernel lock).
> 
> One per CPU?  One lock total?  How many copies of the kernel are running 
one lock.  one kernel.

> at once?  How is caching handled, per cpu, or globally (forcing the two 
> cpu's to look like one?)  When a system call executes, what handles it, 
> one cpu?

caching is handled in hardware with software awareness.  system calls are 
handled by whichever CPU gets scheduled for it..  hence, symmetric.


b3n