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From: Roland Dreier <rdreier@cisco.com>
To: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 1/2] lib: Provide generic atomic64_t implementation
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Cc: linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org,
	Paul Mackerras <paulus@samba.org>, akpm@linux-foundation.org,
	Linus Torvalds <torvalds@linux-foundation.org>
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 > The new Nehalems provide 8 logical threads in a single socket.  All
 > those threads share a cache, and they have cmpxchg8b anyway, so this
 > won't matter.

FWIW, Nehalem EX actually goes to 8 cores/16 threads per socket.  But
worrying about 32-bit performance on Nehalem is a little silly -- this
simplest solution is simply to run a 64-bit kernel.

 - R.