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    Subjectmmap() versus read() and embedded systems.
      Just my $0.02,

    Even if you have memory mapped flash as a file system in an
    embedded environment, with romfs, the main problem is the
    executable loader: it has to modify (resolve address) of the code
    you are executing, so this code has to be copyed first in RAM.
    I am not sure that using static library (instead of ELF) solves
    completely this problem...

    > On Wed, 11 Mar 1998, Michael Lausch wrote:
    > ...
    > > But the problem is when you are using Linux on embedded systems
    > > without any swap (disk) at all. The programs are stored in the FLASH
    > > RAM so the cost of reading a page from the executable is almost zero,
    > > but using a swap area is impossible (no, we don't have 20 Meg RAM for
    > > a RAM swap disk)
    > Is this paged flash or memory mapped flash? Ideally an embedded system
    > would use memory-mapped flash with a filesystem like romfs (? - does it do
    > this?) that would provide it's own mmap that just maps in the page, still
    > in flash, into the process on nopage. This way your executables take up
    > practically no ram under normal circumstances.
    > ...
    > -ben
    -- hdc: irq timeout: status=0xd0 { Busy }
    -- ide1: reset: success
    ----------> I like Linux !

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