Re: [PATCH 2/3] ext4: Context support

On Tue, Jun 12, 2012 at 08:07:28PM +0000, Arnd Bergmann wrote:

Right. The danger here is that the context support was described in
the standard first, while none of the devices seem to even be
smart enough to make use of the information we put in there. Once
operating systems start putting some data in there, at least
some manufacturers will start making use of that data to optimize
the accesses, but it's very unlikely that they will tell us exactly
what they are doing. Having code in ext4 that uses the contexts will
at least make it more likely that the firmware optimizations are
based on ext4 measurements rather than some other file system or
operating system.

From talking with the emmc device vendors, I can tell you that ext4
is very high on the list of file systems to optimize for, because
they all target Android products.

Well, I have a contact at SanDisk where I can discuss things under
NDA, if that will help.  He had reached out to me specifically because
of ext4 and Android --- he's the guy that I invited to give a talk at
the LSF workshop last year.

					- Ted