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Date: Wed, 15 Apr 2009 19:38:06 +0100
From: Jamie Lokier <jamie@shareable.org>
To: Nicolas Pitre <nico@cam.org>
Subject: Re: UBIFS Corrupt during power failure
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Cc: Adrian Hunter <adrian.hunter@nokia.com>,
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Nicolas Pitre wrote:
> On Wed, 15 Apr 2009, Jamie Lokier wrote:
> 
> > Unrelated to this chip: I vaguely remember, aren't there some flash
> > chips which can do more than one block write in parallel, or a write
> > in parallel with an erase to a different block?
> 
> Some NOR flash parts can do a write _or_ an erase in one block while 
> performing any amount of reads in other blocks.  At least that's what we 
> support.  If some parts allow for concurrent writes we currently don't 
> support that.

I don't remember if it was NOR, NAND or something else, but I remember
reading about some flash which supports 1 concurrent write and 1
erase, and thinking "oh that's clever, it means you can do streaming
writes or rapid fsync/database commits without long pauses for erasing".

Of course you can do that with two flash chips side by side :-)

Can MTD and/or UBI join two chips to look like a single partition in
that way and avoid pauses for erase by writing to the other part?

Thanks,
-- Jamie