Carsten Haitzler (The Rasterman) raster at openmoko.org
Tue Jul 8 17:12:51 CEST 2008

On Tue, 08 Jul 2008 15:58:15 +0100 Andy Green <andy at openmoko.com> babbled:

> Hash: SHA1
> Somebody in the thread at some point said:
> | Jffs2 is just a symptom of writing direct to raw NAND...  we don't need
> | to deal with these unusual formats when our storage is SD Card.  In that
> | future, we use the very well characterized ext2 or ext3.
> |
> |> but that doesn't help- as such we have our OS on "on-chip" flash.
> that's where
> |> it is. it's nastily slow (2mb/sec read rates is what i clocked on the
> mtdblock
> |> devices themselves, so bypassing jffs2 overhead). am i wrong i
> suspecting our
> |> flash SHOULD be much faster? (like 5-10x faster)? this is for freerunner.
> |> future devices is... another matter :)
> Well we can boot SD on GTA02.  But I really mean it's not obvious we
> should make a big investment into a new raw mtd filesystem given where
> we are headed.

oooh. no no. i was more thinking of what is out there we already have and what
we can do to it with fairly minimal work to improve it. no big investment.

> Practically, there's likely something wrong with how we use jffs2 from
> cradle to grave and we probably get a better result looking at that.

sure - but i get 2mb/sec of the /dev/mtdblock... devices (using dd). that is
pre-jffs2 so we have also raw mtd device slowness... is 2mb/sec expected from
our 2442?

> - -Andy
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> Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org
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Carsten Haitzler (The Rasterman) <raster at openmoko.org>

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