Re: [PATCH v3] vm_swappiness=0 should still try to avoid swapping anon memory

From: Shakeel Butt
Date: Tue Aug 10 2021 - 17:18:17 EST


On Tue, Aug 10, 2021 at 12:24 PM Nico Pache <npache@xxxxxxxxxx> wrote:
>
>
[...]
> >
> > I'm wondering how you're getting anon scans with swappiness=0. If you
> > look at get_scan_count(), SCAN_FRACT with swappines=0 should always
> > result in ap = fraction[0] = 0, which never yields any anon scan
> > targets. So I'm thinking you're running into sc->file_is_tiny
> > situations, meaning remaining file pages alone are not enough to
> > restore watermarks anymore. Is that possible?
>
> Yes DEACTIVATE_ANON is enabling the file_is_tiny case in shrink_node(). That is what im trying to prevent in the swappiness=0 case.
>

Can you please explain how DEACTIVATE_ANON is enabling the file_is_tiny case?