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Date: Mon, 06 Apr 2009 16:04:06 +0200
From: Aragon Gouveia <aragon@phat.za.net>
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To: Andrew Turner <andrew@fubar.geek.nz>
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Cc: freebsd-embedded@freebsd.org, freebsd-geom@freebsd.org
Subject: Re: FreeBSD NAND flash driver
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Hi,

Andrew Turner wrote:
> Yes, this is intentional as NAND flash is split up to blocks. The
> blocks are then split into pages. You have to erase the entire block at
> a time but can write pages as required. A file system that knows about
> this difference will be able to talk to nand(8) directly.

What I know about file systems and UFS is pretty limited, so forgive me 
if what follows are silly questions.

Are there any defragmentation routines in UFS that could/should be 
disabled when using it on a flash device?  I know a file system can be 
optimized for space or time with tunefs(8).  I imagine optimizing for 
space would be best for a flash device?  Is there anything else other 
than that and your work that can improve flash support?


Thanks,
Aragon