Re: mem=16MB laptop testing

Pavel Machek
2003-10-15T12:12:52Z

Hi!

> > (c) mem= no longer bounds the highest physical address, but rather
> > the sum of memory in e820 entries post-sanitization. This
> > means a ZONE_NORMAL with about 384KB showed up, with duly
> > perverse heuristic consequences for page_alloc.c
>
> I don't understand this. You mean almost all memory was in ZONE_DMA?
>
> "mem=" does not accurately emulate having that much memory. So a 512M box
> booted with "mem=256M" has a different amount of memory from a 256M box
> booted with no "mem=" option. It would be nice to fix that, but I've never
> looked into it.

I do not think this wants to be fixed. It should remain compatible
with 2.4.X, and if it is not that's a bug [and pretty dangerous & hard
to debug one -- if you mark something as ram which is not, you get
real bad data corruption].

Pavel

--
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]