Date: Sat, 19 May 2007 11:25:12 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: William Lee Irwin III <wli@holomorphy.com>
cc: Nick Piggin <npiggin@suse.de>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Linux Memory Management List <linux-mm@kvack.org>,
       linux-arch@vger.kernel.org
Subject: Re: [rfc] increase struct page size?!
In-Reply-To: <20070519181501.GC19966@holomorphy.com>
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On Sat, 19 May 2007, William Lee Irwin III wrote:

> However, there are numerous optimizations and features made possible
> with flag bits, which might as could be made cheap by padding struct
> page up to the next highest power of 2 bytes with space for flag bits.

Well the last time I tried to get this by Andi we became a bit concerned 
when we realized that the memory map would grow by 14% in size. Given 
that 4k page size challenged platforms have a huge amount of page structs 
that growth is significant. I think it would be fine to do it for IA64 
with 16k page size but not for x86_64.


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