Re: [Lhms-devel] Re: [PATCH 2.6.12-rc3 4/8] mm: manual page migration-rc2 -- add-sys_migrate_pages-rc2.patch

[Ray Bryant <raybry@engr.sgi.com>]

Hirokazu Takahashi wrote:
> Hi Ray,
> 
> 

>>
>>Well, what could be done would be the following, I suppose:
>>
>>If follow_page() returns NULL and the vma maps a file, we could
>>lookup the page in the radix tree, and if we find it, and if it
>>is on a node that we are migrating from, we could add the page
>>to the set of pages to be migrated.
>>
>>The disadvantage of this is that we could do a LOT of radix
>>tree lookups and find relatively few pages.  (Our approach of
> 
> 
> 
> How about find_get_pages() for whole mmap()'ed ranges?
> With it, you may not need to call follow_page().
> 

No, you need to call follow_page() to get, for example, the
read-write pages of a shared library that are process private.

For the moment, I would propose punting on this issue.  I don't
think there will be many pages in this category, and if they do
show up later, we have a couple of approaches to deal with them.

-- 
Best Regards,
Ray
-----------------------------------------------
                   Ray Bryant
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The box said: "Requires Windows 98 or better",
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