[H-GEN] Flash drives and wear levelling: user experiences?

Benjamin Fowler somelamer567 at gmail.com
Fri Aug 1 05:54:02 EDT 2008


Hi,

Thanks for all the insightful replies!  With Joel and Clinton's information
in particular, I've got plenty of information to start running with and I'll
definitely have to let everybody know how I get on, perhaps via Planet
HUMBUG, once I get my new blog added (who's maintaining Planet these days).


On Thu, Jul 31, 2008 at 1:21 PM, Clinton Roy <clinton.roy at gmail.com> wrote:

> > My only worry at this stage, is how to go about installing the OS on the
> compact flash card, and configuring everything in such a way, that I don't
> burn holes in the CF card.  Some CF cards allegedly have hardware
> wear-levelling, which is good news (but slooow), but it seems like a good
> idea to try to set everything up so that the amount of writing to the CF
> card is minimised.
>
> The simplest way is to mount root read only and use some tmpfs mounts
> for things that need writing to, like /tmp, /var and /etc
>
> Some rc scripts already have support for this, debian unstable rc
> listens to directives like TMPVARLOCK and TMPVARLOG from
> /etc/default/rc
>
> Some mount commands seem to be able to share the namespace, under
> linux it's simple enough to use unionfs:
>

Clinton's comments are particularly useful.  I plan on using OpenBSD, as if
my memory of reading the OpenBSD documentation serves me correctly, I should
be able to do all this on *BSD as well.

OpenBSD seems like a reasonable choice for a hardened minimalist
distribution for what I have in mind, that is, if you could having a
compiler on a production machine (to keep it patched) "minimalist"...!

Joel's comments on flash cell sizes and write performance were very useful
too, although I've a good mind to have a crack at repeating the experment
myself to check for myself.  I might have a little more work to do to 1)
work out if changing block sizes, or using the striping trick will work on
the filesystems that ship with OpenBSD, and 2) understand what I should be
doing with softupdates/journalling -- my first impulse would be to turn it
off completey to save wear.

Have fun!

Ben.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.humbug.org.au/pipermail/general/attachments/20080801/57febfe8/attachment.html>


More information about the General mailing list