Booting time

[Wolfgang Denk]

Dear Jaap-Jan,

in message <93314AB1-5B9D-11D8-B8DD-000A95B15278 at aimsys.nl> you wrote:
>
> > For a "standard" system with 50 MHz CPU and 50 MHz bus  clock  I  can
> > demonstrate  that  it takes not more than 3...4 seconds from power on
> > until the first application process is running.
>
> What kind of setup is that? A very small ramdisk or flash disk?

This is with a standard setup; root filesystem size is in  the  range
of  5...10 MB. It works with a ramdisk (if not compressed), or with a
MTD based (non-compressing) filesystem. The  second  option  is  more
efficient regarding memory footprint in RAM.

A MTD mounted (read-only) ext2 filesystem in flash is pretty fast.

> Does the (u-) boot loader do extensive ram tests?

Just the basic tests which are also used to auto-size the RAM.

Best regards,

Wolfgang Denk

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