Question about page count

[Mulyadi Santosa]

Hi...

On 20/06/2011, Jui-Hao Chiang <windtracekimo at gmail.com> wrote:
> Hi,
>
> I am currently analyzing the memory pages footprint in 2.6.18.8 kernel (1GB
> ram,
> 32-bit, Flat model, no NUMA), and got a question. Does page_count(page)==0
> really means the page is free because the source code says so?

looking at how page_count implemented, it checks whether the related
page is gonna be reclaimed or a compound page (not sure what it is).
If so, returns the first page of that "page".

by comparing the definition of free page as "really free, not being
used for any purpose" versus the above perception, I guess it's not
surprising to see the difference

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com