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Re: Embedded database recommendation?



"Mikael Starvik" <mikael.starvik@xxxxxxx.com> writes:

> >takes the characteristics of NOR flash into account.
> >That could in theory give me a _very_ robust database that doesn't
> >wear out the flash unnecesarily.
> 
> JFFS2 has wear-leveling that takes the characteristics of NOR flash
> into account but maybe it can be done in a better way. What you
> really need if you write often is a battery backed-up RAM that you
> sync to flash now and then. Another way is of course to use a disk...

Yes, JFFS2 is still limited by the Linux page cache.  It has to either
write a whole page at a time or it has to do a compare of the old and
new page contents and only write the changed bytes to flash.  So a
dedicated NOR flash database engine would have an easier time of
optimizing flash writes.

  /Christer

-- 
"Just how much can I get away with and still go to heaven?"

Freelance consultant specializing in device driver programming for Linux 
Christer Weinigel <christer@xxxxxxx.se">http://www.weinigel.se