Dave,
....snip....
> Hmmm.... there's a scenario I didn't count on. Do the SD cards suffer
> from the same fate ?
> >
> > I wish you well. If you have time I'd be interested in an outline of
> > what you end up doing and how it performs in practice.
>
> By the sounds of it whatever I do will have random results...
I've done a little more reading on this stuff and I'm not too sure that
any pre-allocation/pre-written schemes are going to make much difference -
but I've not thought it all thru' completely.
I think anyone planning on optimising writes to CF/SD/USB flash sticks
should really take time to understand how the writes are organised
in a NAND flash, and to try and get an overview of what the controller
does that sits between the CF/CD/USB interface and the Flash chips!
These things are not like Hard Drives.
The problem is that some of the important stuff that you'd maybe like
to know to optimise writes (like flash erase block size) jsut isn't
published.
Here are some of the web sites I found interesting stuff at....
http://www.gatago.com/linux/kernel/6108739.html
A linux-kernel email list thread on flash memories. Some excellant
explanations on how flash memory works. Takes a bit of getting thru'
but worth it.
hhttp://en.wikipedia.org/wiki/Flash_Memory
An introduction to how Flash memory works and is organised
ttp://www.cyberguard.info/snapgear/tb20020917.html
Technical Bulletin #13 - Using Flash Memory with uClinux
http://www.trustedreviews.com/article.aspx?art=3173
Comparison of a selection of 2GB SD and 4GB CF flash memory cards
http://www.st.com/stonline/products/literature/ds/10058.htm
STMicroelectronics NAND Flash memories and related Application Notes
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