Re: [BK PATCH 2.5] Introduce 64-bit versions of PAGE_{CACHE_,}{MASK,ALIGN}

[Andrew Morton <akpm@zip.com.au>]

Rik van Riel wrote:
> 
> On Mon, 29 Jul 2002, Andrea Arcangeli wrote:
> 
> > if you look at DaveM first full rmap implementation it never had a
> > pte-chain. He used the same rmap logic we always hand in linux since the
> > first 2.1 kernel I looked at, to handle correctly truncate against
> > MAP_SHARED. Unfortunately that's not very efficient and requires some
> > metadata allocation for anonymous pages (that's the address space
> > pointer, anon pages regularly doesn't have a dedicated address space),
> 
> Together with the K42 people we found a way to avoid the
> badnesses of an object-based VM.
> 

eek.  Please let's not tie the delivery of the 2.6 kernel to
the success of this R&D effort.  We need reasonable-sized fixes, fast,
for the current problems so that people who have feature work banked
up can get going on it.

Plus, staying close to the 2.4 rmap VM allows us to leverage the
testing and experience which that has had, yes?

-