On Tue, 4 Jan 2000, Rik van Riel wrote:

d+r+h > limit
d     > limit/2
r     > limit/4
h     > limit/8

Ehmmm, wait. I messed up on this one.
We probably want to have a bit more freedom
so the page freeing algorithm doesn't do too
much scanning for nothing.

d+r+h 	> limit
d	> limit/4
r	> limit/4
h	don't care, even on a 1.5GB machine h will
	be 1/3 of total memory, so we'll usually
	have a few free pages in here

DMA pages should always be present, regular pages for
storing pagetables and stuff need to be there too, higmem
pages we don't really care about.

Btw, I think we probably want to increase freepages.min
to 512 or even more on machines that have >1GB of memory.
The current limit of 256 was really intended for machines
with a single zone of memory...

(but on <1GB machines I don't know if it makes sense to
raise the limit much more ... maybe we should raise the
limit automagically if the page alloc/io rate is too
high?)

Rik
--
The Internet is not a network of computers. It is a network
of people. That is its real strength.

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.nl.linux.org/Linux-MM/