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Subject: Re: Comparing UBI volumes to generate patch for upgrades
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Subodh Nijsure <snijsure@grid-net.com>
Date: Fri, 03 Feb 2012 11:18:23 +0200
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On Wed, 2012-02-01 at 10:31 -0800, Subodh Nijsure wrote:
> one option is  use VCDIFF/bsdif or variation there-of and generate a=20
> binary diff package.
>=20
> option 2 is write a tool that compares UBI volume layout for revision 1=
=20
> and UBI volume layout for revision 2 and then send that difference,=20
> along the lines of what is outlined in the paper @=20
> http://www.icmu.org/icmu2010/Papers/3-1.pdf

I guess you can do this for R/O volumes, but not R/W.

Depending on how much extra flash you have, you may do the actual update
in a power-off-tolerant manner or not.

> We are just getting started writing a tool to compare UBI volumes, but I=
=20
> want to send out querry to UBI experts to see if there are some=20
> fundamental issues with UBI that would make comparing UBI volumes and=20
> applying such a patch would be a non-starter.

I assume you are not planning to do this stuff in kernel space, right?

--=20
Best Regards,
Artem Bityutskiy


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