Subject: Re: Do some disk accesses miss the UVM?
To: Chuck Silvers <chuq@chuq.com>
From: Perry E. Metzger <perry@wasabisystems.com>
List: tech-kern
Date: 01/26/2002 12:59:42
Chuck Silvers <chuq@chuq.com> writes:
> actually the generational idea isn't a replacement for the knobs.
> the generational bit still depends on the assumption that past behaviour
> is a good predictor of future behaviour, so it falls down just like the
> pre-knob code when that assumption isn't true.

Absolutely, but *every* policy does. The best part of the research of
the last 30 years on the subject is the realization that even if you
have a psychic computer that knows what the entire future of page use
will be, in the most general case it is still extremely
computationally expensive to determine what pages to evict.


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Perry E. Metzger		perry@wasabisystems.com
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