[question] call mark_page_accessed() in minor fault

[Zheng Liu <gnehzuil.liu@gmail.com>]

Hi all,

Recently we meet a performance regression about mmaped page.  When we upgrade
our product system from 2.6.18 kernel to a latest kernel, such as 2.6.32 kernel,
we will find that mmaped pages are reclaimed very quickly.  We found that when
we hit a minor fault mark_page_accessed() is called in 2.6.18 kernel, but in
2.6.32 kernel we don't call mark_page_accesed().  This means that mmaped pages
in 2.6.18 kernel are activated and moved into active list.  While in 2.6.32
kernel mmaped pages are still kept in inactive list.

So my question is why we call mark_page_accessed() in 2.6.18 kernel, but don't
call it in 2.6.32 kernel.  Has any reason here?

Thanks in advance,
						- Zheng

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