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Date: Tue, 12 Feb 2002 20:00:41 -0200 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: William Lee Irwin III <wli@holomorphy.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, <linux-kernel@vger.kernel.org>
Subject: Re: File BlockSize
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On Tue, 12 Feb 2002, William Lee Irwin III wrote:
> On Tue, Feb 12, 2002 at 02:37:43PM +0000, Alan Cox wrote:
> > Going to a block size bigger than page size causes all sorts of fun with
> > allocation failures if there are not two pages free adjacent to one another
> > when allocating, and isn't really worth the cost.
>
> This sounds like fairly severe memory fragmentation, which seems more
> worrisome to me than blocksize constraints. Should I look into that?

Sorry for being dense, but I don't see why an 8 kB block would
need to occupy 2 contiguous pages in ram.

The page cache is indexed in pages, it should be easy enough to
do the disk IO on the 8 kB on-disk block as 2 4 kB IOs, each to
a different page in RAM.

regards,

Rik
-- 
"Linux holds advantages over the single-vendor commercial OS"
    -- Microsoft's "Competing with Linux" document

http://www.surriel.com/		http://distro.conectiva.com/

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