Re: Compact Flash Question

[Mark Lord <liml@rtr.ca>]

Bart Van Assche wrote:
> On Wed, May 7, 2008 at 5:01 PM, Stéphane ANCELOT <sancelot@free.fr> wrote:
>> we use  silicon systems CF  with wear leveling inside  , we write a few
>> kb data back each 1/4 h  on it.(log /tmp files  are redirected to ram)
> 
> Silicon Systems CompactFlashes are the among the most reliable
> CompactFlashes I have used in embedded devices. See also
> http://www.siliconsystems.com/silicondrive/whitepapers/SSWP03-Endurance-R.pdf
> for a whitepaper that explains their wear leveling and error
> correction algorithms. Furthermore, Silicon Systems has a technology
> called SiSMART that allows to monitor by how far the CompactFlash is
> worn out, such that it can be monitored whether or not it is time to
> replace the CompactFlash. (Note: I am not affiliated in any way to
> Silicon Systems.)
..

Mmm.. according to that document, the "dynamic wear leveling" devices
might benefit from having Linux issue CF-Erase commands to unallocated sectors,
so that the onboard CF controller can then add those sectors to the wear-leveling
rotation scheme.

There was discussion at LSF'08 about possible filesystem hooks that could
be used for this (and other) purposes when deleting files.

Cheers