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Altera_Forum's avatar
Altera_Forum
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20 years ago

Memory footprint

What are the typical size ranges you can expect for the Kernal. How much working memory does it require.

My feeling is 2Meg for the Kernal and 4 Meg total for RAM should do it. Does that seem reasonable?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    I build out the file"vmlinux" 7.41 MB (minimize)

    and the kernel is 777kB after uclinux working.

    what about the relationship about them(vmlinux and kernel)? why not they are the same size?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    Hi mountain8848,

    > what about the relationship about them(vmlinux and kernel)?

    > why not they are the same size?

    vmlinux is an elf file and it contains lots of extra linker sections like comments and debug

    information that are not allocated space in your memory. For example, my vmlinux size is

    about 11 MB, but the allocated memory (in the elf) is about 1.3 MB.

    You can get a better sense for the amount of memory your kernel code will occupy

    by stripping the elf:

    $ nios2-elf-strip vmlinux

    Or you can just use objdump and add up the sections that have the ALLOC attribute.

    But note that this does not account for any dynamic memory that may be needed.

    Regards,

    --Scott