Re: Have ext3 on SanDisk CF but can't disable write-back caching as kernel instructs

From: Dan Harkless (usenet_at_harkless.org)
Date: 07/17/03 

Date: 16 Jul 2003 16:33:20 -0700

Bernhard Roessmann <roessmann@gmx.net> wrote in message
news:<bem328$6jri3$1@ID-49938.news.uni-berlin.de>:
> > Our device may lose power at any time, but it's very important we
> > don't corrupt our data or our filesystem metadata, so our filesystems
> > (except our initrd-based root filesystem) are ext3, mounted
> > 'data=journal'.
>
> I don't think that it is a good idea to use ext3 on a CF.
> ext3 does MANY writes to the journal, so the CF will possibly wear out
> very soon.

Forgot to address this in my previous reply -- when you say "MANY",
are you saying an ext3 filesystem on CF will get written to on the
order of 2-3x as much as an ext2 filesystem would get written to? Or
are you saying it'll get written to an order of magnitude more?

If not the latter, I don't think we care. Our preliminary ad-hoc
calculations based on how we *hope* the SanDisk wear-leveling works
(today I was told they'll supposedly be getting back to us within a
week with details on that) showed the CF ought to last in the
thousands of years. 

--
Dan Harkless
usenet@harkless.org
http://harkless.org/dan/

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