Re: Ideas for memory management hackers.

[Rik van Riel <H.H.vanRiel@fys.ruu.nl>]

On Tue, 9 Dec 1997, Stephen Thomas wrote:

> Should vhand have any effect on memory utilisation figures,
> as reported by /proc/meminfo?  If so, then vhand did not seem
> to be achieving much, for all its hard work ...

I have integrated mmap aging in kswapd, without the need for
vhand, in 2.1.71 (experimental). As ppp isn't working in 2.1.71
I'm back to 2.1.66 now, but I have seen kswapd use over 10% of
CPU for short times now :(

But it doesn't have the disadvantage of having to scan constantly,
and it seemed to work better than vhand (it seems that page->accessed
isn't updated automatically, and has to be done via pte->flags in
the page-table scanning done by kswapd... This would vhand have
a fundamental design flaw, which would explain why some people
saw a boost in performance, while others saw performance worsen...

I think I'll send it to Linus (together with Zlatko's
big-order hack) as a bug-fix (we're on feature-freeze after all:)
for inclusion in 2.1.72...

opinions please,

Rik.

--
Send Linux memory-management wishes to me: I'm currently looking
for something to hack...