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From: Arnd Bergmann <arnd@arndb.de>
To: joern@logfs.org
Subject: Re: [patch 10/15] fs/logfs/memtree.c
Date: Thu, 10 Apr 2008 16:07:44 +0200
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	<20080401181332.853833010@logfs.org>
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On Tuesday 01 April 2008, joern@logfs.org wrote:
> +#if BITS_PER_LONG =3D=3D 32
> +#define BTREE_NODES 20=A0/* 32bit, 240 byte nodes */
> +#else
> +#define BTREE_NODES 16=A0/* 64bit, 256 byte nodes */
> +#endif
> +
> +struct btree_node {
> +=A0=A0=A0=A0=A0=A0=A0u64 key;
> +=A0=A0=A0=A0=A0=A0=A0struct btree_node *node;
> +};

On 32 bit platforms other than x86, your struct btree_node
is 16 bytes long because of alignment requirements, rather
than the 12 bytes you are assuming.

	Arnd <><