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Date: Thu, 6 Mar 2003 12:05:48 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Davide Libenzi <davidel@xmailserver.org>
cc: linux-kernel@vger.kernel.org
Subject: Re: HT and idle = poll
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On Thu, 6 Mar 2003, Davide Libenzi wrote:
> 
> Not only. The polling CPU will also shoot a strom of memory requests,
> clobbering the CPU's memory I/O stages.

Well, that would only be true with a really crappy CPU with no caches.

Polling the same location (as long as it's a pure poll, not trying to do 
some locked read-modify-write cycle) should be fine. At least for 
something like idle-polling, where the one location it _is_ polling should 
not actually be touched by anybody else until the wakeup actually happens.

		Linus

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