Re: VM in 2.4.7-pre hurts...

Rik van Riel
2001-07-07T20:12:19Z

On Sat, 7 Jul 2001, Linus Torvalds wrote:

> In fact, I do not see any part of the whole path that sets the
> page age at all, so we're basically using a completely
> uninitialized field here (it's been initialized way back when
> the page was allocated, but because it hasn't been part of the
> normal aging scheme it has only been aged up, never down, so the
> value is pretty much random by the time we actually add it to
> the swap cache pool).

Not quite. The more a page has been used, the higher the
page->age will be. This means the system has a way to
distinguish between anonymous pages which were used once
and anonymous pages which are used lots of times.

> Suggested fix:

[snip disabling of page aging for anonymous memory]

> That would certainly help explain why aging doesn't work for some people.

As would your patch ;)

regards,

Rik
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