Subject: Re: [ckrm-tech] [RFC][PATCH 5/7] UBC: kernel
	memory	accounting	(core)
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Kirill Korotaev <dev@sw.ru>
Cc: rohitseth@google.com, Dave Hansen <haveblue@us.ibm.com>,
       Rik van Riel <riel@redhat.com>, ckrm-tech@lists.sourceforge.net,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Christoph Hellwig <hch@infradead.org>, Andrey Savochkin <saw@sw.ru>,
       devel@openvz.org, hugh@veritas.com, Ingo Molnar <mingo@elte.hu>,
       Pavel Emelianov <xemul@openvz.org>, Andi Kleen <ak@suse.de>
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Date: Fri, 18 Aug 2006 15:59:25 +0100
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Ar Gwe, 2006-08-18 am 12:52 +0400, ysgrifennodd Kirill Korotaev:
> > hmm, not sure why it is simpler.
> because introducing additonal lookups/hashes etc. is harder and
> adds another source for possible mistakes.
> we can always optimize it out if people insist (by cost of slower accounting).

It ought to be cheap. Given each set of page structs is an array its a
simple subtract and divide (or with care and people try to pack them
nicely for cache lines - shift) to get to the parallel accounting array.

Alan

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