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Date: Fri, 04 Dec 2009 13:31:12 +0200
From: Adrian Hunter <adrian.hunter@nokia.com>
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To: twebb <taliaferro62@gmail.com>
Subject: Re: ubifs wear leveling across entire device
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twebb wrote:
> I'm confused about how wear leveling occurs across the entire device
> in the following example.  Could someone help me understand what I'm
> missing?
> 
> 4 GiB flash device (nand MLC):
> 4 MTD partitions defined:
> 0 - "p1" - 0x00000000 - 0x00800000
> 1 - "p2" - 0x00800000 - 0x10000000
> 2 - "p3" - 0x10000000 - 0x80000000
> 3 - "p4" - 0x80000000 - 0x100000000
> 
> kernel args specify 3 ubi volumes:
> ubi.mtd=p1 ubi.mtd=p2 ubi.mtd=p3
> (p4 is reserved and no volumes or filesystems sit on top of it)

That is 3 UBI devices not 3 UBI volumes

> 
> The "vol_size" for each of the ubi volumes (as specified in the
> ubinize cfg file) is slightly less than the corresponding mtd
> partition size.  The volumes are specified as dynamic because they
> need to be RW.