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From: David Woodhouse <dwmw2@infradead.org>
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In-Reply-To: <20011118202252.A8708@vger.timpanogas.org>  <200111181710.fAIHAlCF011794@sleipnir.valparaiso.cl> <Pine.LNX.4.33.0111181803040.7482-100000@penguin.transmeta.com> 
To: "Jeff V. Merkey" <jmerkey@vger.timpanogas.org>
Cc: Linus Torvalds <torvalds@transmeta.com>,
        Horst von Brand <vonbrand@sleipnir.valparaiso.cl>,
        Andrea Arcangeli <andrea@suse.de>, ehrhardt@mathematik.uni-ulm.de,
        linux-kernel@vger.kernel.org
Subject: Re: VM-related Oops: 2.4.15pre1 
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Date: Mon, 19 Nov 2001 08:44:28 +0000
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jmerkey@vger.timpanogas.org said:
>  This is true.  They Generate what's called a "split lock" bus
> transaction where the bus will hold LOCK# low across the several clock
> cycles to  complete the write.  They are **VERY** heavy, BTW, and
> really cause  nasty performance hits. 

Is it worth making put_unaligned and get_unaligned on x86 avoid this by 
loading/storing the two halves of the required datum separately, then? 

--
dwmw2


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