From mboxrd@z Thu Jan  1 00:00:00 1970
From: Coywolf Qi Hunt <coywolf@gmail.com>
Subject: Re: [PATCH] struct file cleanup : the very large file_ra_state is now allocated only on demand.
Date: Thu, 18 Aug 2005 09:39:16 +0800
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Cc: Andi Kleen <ak@suse.de>, Benjamin LaHaise <bcrl@linux.intel.com>,
	"David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
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To: Eric Dumazet <dada1@cosmosbay.com>
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On 8/18/05, Eric Dumazet <dada1@cosmosbay.com> wrote:
> Andi Kleen a =E9crit :
>=20
> >
> >>(because of the insane struct file_ra_state f_ra. I wish this struc=
ture
> >>were dynamically allocated only for files that really use it)
> >
> >
> > How about you submit a patch for that instead?
> >
> > -Andi
>=20
> OK, could you please comment this patch ?
>=20
> The problem of dynamically allocating the readahead state data is tha=
t the allocation can fail and should not be fatal.
> I made some choices that might be not good.
>=20
> I also chose not to align "file_ra" slab on SLAB_HWCACHE_ALIGN becaus=
e the object size is 10*sizeof(long), so alignment would loose
> 6*sizeof(long) bytes for each object.
>=20
>=20
> [PATCH]
>=20
> * struct file cleanup : the very large file_ra_state is now allocated=
 only on demand, using a dedicated "file_ra" slab.
>         64bits machines handling lot of sockets can save about 72 byt=
es per file.
> * private_data : The field is moved close to f_count and f_op fields =
to speedup sockfd_lookups

Why not keep the comment or fix it?

--=20
Coywolf Qi Hunt
http://ahbl.org/~coywolf/