From owner-freebsd-current@FreeBSD.ORG  Thu May 25 17:36:16 2006
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To: "Andrew Atrens" <atrens@nortel.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 25 May 2006 13:30:04 EDT."
	<4475E99C.5000502@nortel.com> 
Date: Thu, 25 May 2006 19:36:09 +0200
Message-ID: <3981.1148578569@critter.freebsd.dk>
Sender: phk@critter.freebsd.dk
Cc: Alexander Leidinger <Alexander@Leidinger.net>,
	Jim Thompson <jim@netgate.com>, small@freebsd.org, current@freebsd.org
Subject: Re: FreeBSD's embedded agenda 
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In message <4475E99C.5000502@nortel.com>, "Andrew Atrens" writes:
>-----BEGIN PGP SIGNED MESSAGE-----
>Hash: SHA1
>
>Seems to me you'd want a kernel that could boot off raw
>flash and run in RAM off a small RAM disk.
>
>Said kernel would have a low level driver that makes plain
>old flash chips look (and behave) like a disk. It would support
>wear-levelling, [...]
>
>Then you could throw FFS on top of that.

This is exactly what you do not want to do.

You want to write a flash friendly filesystem which knows what
a flash is, and which does the wear levelling internally.

The reason Flash Adaptation Layers came about in the first place
is that W95 didn't support anything but FAT.

Don't propagate that mistake.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.