lkml.org 
[lkml]   [2011]   [Feb]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC][PATCH 2/6] pagewalk: only split huge pages when necessary
On Mon, Jan 31, 2011 at 04:33:59PM -0800, Dave Hansen wrote:
>
> Right now, if a mm_walk has either ->pte_entry or ->pmd_entry
> set, it will unconditionally split and transparent huge pages
> it runs in to. In practice, that means that anyone doing a
>
> cat /proc/$pid/smaps
>
> will unconditionally break down every huge page in the process
> and depend on khugepaged to re-collapse it later. This is
> fairly suboptimal.
>
> This patch changes that behavior. It teaches each ->pmd_entry
> handler (there are three) that they must break down the THPs
> themselves. Also, the _generic_ code will never break down
> a THP unless a ->pte_entry handler is actually set.
>
> This means that the ->pmd_entry handlers can now choose to
> deal with THPs without breaking them down.

Makes perfect sense. But you forgot to push down the splitting into
the two handlers in mm/memcontrol.c.


\
 
 \ /
  Last update: 2011-02-01 11:07    [W:0.114 / U:16.024 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site