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Subject: Re: MTD RAID
From: Artem Bityutskiy <dedekind1@gmail.com>
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Date: Mon, 22 Aug 2016 10:27:21 +0300
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On Mon, 2016-08-22 at 11:22 +0800, Dongsheng Yang wrote:
> As I explained above, MTD RAID is not just a solution for reliability
> problem for MLC/TLC. 

Could you please answer these questions.

1. Does MTD raid work on MLC or is it SLC-only?

2. If I am building RAID-0, I have 2 flash chips, one has every even
block bad, the other has every odd block bad. What happens?

3. Same question, but for RAID-1.

4. Suppose I have RAID-1 like in this picture:

https://en.wikipedia.org/wiki/Standard_RAID_levels#/media/File:RAID_1.svg

Just assume we have flash chips, not disks, and eraseblocks, not
sectors.

Suppose eraseblock A1 goes bad. What happens next?


5. Suppose I have RAID-0 like here:

https://en.wikipedia.org/wiki/Standard_RAID_levels#/media/File:RAID_0.svg

Again, we are talking about chips and eraseblocks here.

What happens if A1 goes bad.

Thanks!