This is not an important question, I'm just curious. Something strange happened, which isn't quiet clear to me:
In the kernel command line, the amount of the memory can be set statically with the
mem=128M (for 128 MB). If the
mem command is left out, I believe the kernel figures this out by itself.
Now, when I leave out the
mem command, the Linux boots in
6.906 s. If I put it to the max. of RAM statically, that too leads to
6.906 s startup time, same with
80 MB and some other values.
But if I set
50 MB or
60 MB the system boots in
6.775 s (that's a
130 ms shorter startup time). But why ? Does it need less time for searching if there isn't much space left to look for?
[Edit:] The time was measured on an embedded System with the help of a scope and a GPIO pin, which was set 'high' at very first command in the 1st-lvl-Bootloader, and was set to 'low' in the last script of
An ARM9 SAM9G25 was used with 400 MHz (for further information about the CPU here's a link with its paramters link)