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Re: cached cramfs?



> > The compressed parts of flash (including /) are copied to RAM at
> > boottime, so this shouldn't matter.
>
>
> Are you _realy_ sure of that? If so, where does it happen? I can't find
> it out. The compressed kernel are copied to ram thought, that I can see.

Oops, sorry! Filesystem caching seems to work so well that just copying some
files to ramdisk doensn't necessarily create activity on flash /CS.
Compressed kernel and cramfs image reside on the same partition but they are
_not_ compressed at the same time, making it possible to read just
individual files, of course..

But back to the original question, where's the point? Data is decompressed
to RAM anyway and run there. The bus would run in bursts with cache, but at
least the flash chip that comes with Devboard LX doesn't benefit from
bursting at all. (Due to instruction execution there seems to be a  30ns gap
between single read accesses to flash, but these would occur anyway after a
full line has been read to cache.)


Jarkko