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Subject: Re: Anticipatory prefaulting in the page fault handler V1
From: Dave Hansen <haveblue@us.ibm.com>
To: Christoph Lameter <clameter@sgi.com>
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On Wed, 2004-12-08 at 09:24, Christoph Lameter wrote:
> The page fault handler for anonymous pages can generate significant overhead
> apart from its essential function which is to clear and setup a new page
> table entry for a never accessed memory location. This overhead increases
> significantly in an SMP environment.

do_anonymous_page() is a relatively compact function at this point. 
This would probably be a lot more readable if it was broken out into at
least another function or two that do_anonymous_page() calls into.  That
way, you also get a much cleaner separation if anyone needs to turn it
off in the future.  

Speaking of that, have you seen this impair performance on any other
workloads?  

-- Dave