Re: [PATCH 1/1] mm: vmscan: Reduce throttling due to a failure to make progress

Mel Gorman
2021-11-29T08:29:02Z

On Sun, Nov 28, 2021 at 11:00:59AM +0100, Mike Galbraith wrote:
> On Sun, 2021-11-28 at 04:26 +0900, Alexey Avramov wrote:
> > I will present the results of the new tests here.
> >
> > TLDR;
> > =====
> > No one Mel's patch doesn't prevent stalls in my tests.
>
> Seems there may be a problem with the THROTTLE_WRITEBACK bits..
>
> > $ for i in {1..10}; do tail /dev/zero; done
> > -- 1. with noswap
>
> ..because the bandaid below (made of 8cd7c588 shards) on top of Mel's
> last pulled that one-liner's very pointy fangs.
>

This disables writeback throttling in most cases as bdi congested is not
updated by the block layer.

--
Mel Gorman
SUSE Labs