Re: why the count nr_file_pages is not equal to nr_inactive_file + nr_active_file ?

From: Michal Hocko
Date: Mon May 16 2016 - 07:16:34 EST


On Mon 16-05-16 18:01:40, Xishi Qiu wrote:
> On 2016/5/16 17:57, Michal Hocko wrote:
>
> > [Sorry I haven't noticed this answer before]
> >
> > On Fri 13-05-16 15:31:42, Xishi Qiu wrote:
> >> On 2016/5/13 15:00, Aaron Lu wrote:
> >>
> >> Hi Aaron,
> >>
> >> Thanks for your reply, but I find the count of nr_shmem is very small
> >> in my system.
> >
> > which kernel version is this? I remember that we used to account thp
> > pages as NR_FILE_PAGE as well in the past.
> >
> > I didn't get to look at your number more closely though.
>
> Hi Michal,
>
> It's android kernel, v3.10
> I think the thp config is off.

Ble. Not enough sleep. I didn't mean thp but hugetlb pages. Sorry about
the confusion. If even that is not the case then there is either an
accounting bug or some fs doesn't put pages in the pagecache directly to
the LRUs or thos pages are on unevictable list.
--
Michal Hocko
SUSE Labs