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Subject: Re: [RFC][patch] NAND partial page read functionality
From: Artem Bityutskiy <dedekind@infradead.org>
To: Thomas Gleixner <tglx@linutronix.de>, David Woodhouse <dwmw2@infradead.org>
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Date: Thu, 24 Apr 2008 10:11:55 +0300
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Cc: Hamish Moffatt <hamish@cloud.net.au>, linux-mtd@lists.infradead.org,
	Alexey Korolev <akorolev@infradead.org>
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Hi David, Thomas,

On Thu, 2008-04-24 at 09:34 +0300, Artem Bityutskiy wrote:
> On Thu, 2007-12-13 at 18:15 +0000, Alexey Korolev wrote:
> > Hi=20
> >=20
> > Here is a patch providing partial page read functionality for NAND
> > devices.=20
> >=20
> > In many cases it gives performacne boost. I've added this feature
> > enabling under chip->options flag.=20
> > Setting NAND_PART_READ option in board driver will enable this feature.
>=20
> Hamish, this stuff should certainly help you. You could give it a try.
> Unfortunately Alexey gave up almost straight away and did not try to
> push his work harder.The arguments against the patch were weak, and
> addressable. This work needs some more efforts and it may get merged.
> Moreover, Alexey came with impressive numbers, and it is difficult to
> argue against. Would you give it a try? If it gives performance benefits
> for you, I think we could raise this again.
>=20
> Look here for the full story:=20
> http://lists.infradead.org/pipermail/linux-mtd/2007-December/020105.html

Could we please take a look at this work:
http://lists.infradead.org/pipermail/linux-mtd/2007-December/020105.html

and identify what should be changed/done to have it merged. Alexey shows
impressive numbers there. Also, Hamish(*) shows that UBI attach time drops
from about 5.6 seconds to about 2.5 seconds which is a very substantial
growth.

Thanks!

*) http://lists.infradead.org/pipermail/linux-mtd/2008-April/021413.html

--=20
Best regards,
Artem Bityutskiy (=D0=91=D0=B8=D1=82=D1=8E=D1=86=D0=BA=D0=B8=D0=B9 =D0=90=
=D1=80=D1=82=D1=91=D0=BC)