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Re: Is JFFS a full featured filesystem?

On Wed, 2 Aug 2000, David Woodhouse wrote:

> alex@xxxxxxx.se said:
> >  This could cause consistancy problems though, because we're not using
> > the (possibly modified) mmaped data when writing directly to a file,
> > we also in some way guarantee that all writes are done to the log in
> > the correct order. It will also be an inefficient way to write data to
> > jffs, since we have to rewrite whole pages instead of only the written
> > part.
> I believe that we can address both of those problems - we can write data 
> directly from the page cache and we can also work out which ranges within
> a page have actually been dirtied. 

What about the log-ordering constraints? That kinda voids any write
caching at all. It could possibly be solved using a kernel thread that
does all the flash writing (in a serialized fashion), but the caching
problems get a lot harder then.

/ Ale