Re: [RFC][PATCH 0/3] beat kswapd with the proverbial clue-bat

Linus Torvalds
2004-09-05T17:24:57Z

On Sun, 5 Sep 2004, Nick Piggin wrote:
>
> Hmm, and the crowning argument for not stopping at order 3 is that if we
> never use higher order allocations, nothing will care about their watermarks
> anyway. I think I had myself confused when that question in the first place.
>
> So yeah, stopping at a fixed number isn't required, and as you say it keeps
> things general and special cases minimal.

Hey, please refute my "you need 20% free" to get even to order-3 for most
cases first.

It's probably acceptable to have a _very_ backgrounded job that does
freeing if order-3 isn't available, but it had better be pretty
slow-moving, I suspect. On the order of "It's probably ok to try to aim
for up to 25% free 'overnight' if the machine is idle" but it's almost
certainly not ok to aggressively push things out to that degree..

Linus