Re: page_launder() on 2.4.9/10 issue

[Linus Torvalds]

On Tue, 28 Aug 2001, David S. Miller wrote:
>
>    At least something seems to be broken in it. I did run some 900MB processes
>    on a 512MB machine with 2.4.9 and kswapd took between 70 and 90% of the CPU
>    time.
>
> That's all swapmap lookup stupidity, you'll see __get_swap_page()
> near the top of your profiles.  The algorithm is just sucky.

Well, in all fairness the kswapd changes _do_ make kswapd more eager to
keep running too (ie kswapd tends to keep running until there is no
shortage any more - which it traditionally hasn't really done).

There might be an argment for making kswapd less eager, and more of a
background thing.

Regardless of where it actually spends the CPU time.

		Linus