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Date: Tue, 25 Feb 2003 12:53:44 -0800
From: "Martin J. Bligh" <mbligh@aracnet.com>
To: Andrea Arcangeli <andrea@suse.de>
cc: William Lee Irwin III <wli@holomorphy.com>, Andrew Morton <akpm@digeo.com>,
       Hanna Linder <hannal@us.ibm.com>, lse-tech@lists.sf.et,
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Subject: Re: Minutes from Feb 21 LSE Call
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>> > the only solution is to do rmap lazily, i.e. to start building the rmap
>> > during swapping by walking the pagetables, basically exactly like I
>> > refill the lru with anonymous pages only after I start to need this
>> > information recently in my 2.4 tree, so if you never need to pageout
>> > heavily several giga of ram (like most of very high end numa servers),
>> > you'll never waste a single cycle in locking or whatever other
>> > worthless accounting overhead that hurts performance of all common
>> > workloads
>> 
>> Did you see the partially object-based rmap stuff? I think that does
>> very close to what you want already.
> 
> I don't see how it can optimize away the overhead but I didn't look at
> it for long.

Because you don't set up and tear down the rmap pte-chains for every 
fault in / delete of any page ... it just works off the vmas.

M.

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