XIP has one other major requirement that Android doesn't fulfil - native
code.  95% of what executes on android is java bytecode, so mmap is a much
bigger gain than XIP.

On Mon, Dec 8, 2008 at 9:31 PM, Jean-Baptiste Queru <[EMAIL PROTECTED]> wrote:

>
> If I understand correctly XIP requires a NOR flash (i.e. essentially
> byte-addressable), whereas a plain mmap works happily with a simpler
> NAND flash (block-addressable). Not relying on having a NOR flash
> increases the range of devices that Android might work on.
>
> In addition, flash performance is typically an order of magnitude or
> two below RAM performance. The only way to realistically deal with
> that fact would be to make an in-RAM copy of the XIP data... which
> would negate any and all memory size gain compared to a plain mmap
> solution.
>
> Regards,
> JBQ
>
> On Mon, Dec 8, 2008 at 6:14 PM, Mihai Fonoage <[EMAIL PROTECTED]> wrote:
> > Hello everyone,
> >
> > I am not sure if this is the right place to post this question. I posted
> > first in the Android Internals group, but I read that the message list is
> > closing. If you knwo of a better place to ask this question, please let
> me
> > know.
> >
> > My question: is the concept of Execute in Place used with the Dalvik VM?
> I
> > know that the concept of clean memory via the mmap() system call is used,
> > but I believe that even with that, XIP is not used (as opposed to Windows
> > Mobile). Can you please clarify this?
> >
> > Thank you!
> >
> > Mihai Fonoage
> >
> > >
> >
>
> >
>

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