Re: [PATCH v4 1/1] mm: vmscan: Reduce throttling due to a failure to make progress'

Shuang Zhai
2022-02-22T17:28:30Z

Mel Gorman wrote:
> On Mon, Feb 14, 2022 at 04:10:50PM -0500, Shuang Zhai wrote:
> > Hi Mel,
> >
> > Mel Gorman wrote:
> > >
> > > Mike Galbraith, Alexey Avramov and Darrick Wong all reported similar
> > > problems due to reclaim throttling for excessive lengths of time.
> > > In Alexey's case, a memory hog that should go OOM quickly stalls for
> > > several minutes before stalling. In Mike and Darrick's cases, a small
> > > memcg environment stalled excessively even though the system had enough
> > > memory overall.
> > >
> >
> > I recently found a regression when I tested MGLRU with fio on Linux
> > 5.16-rc6 [1]. After this patch was applied, I re-ran the test with Linux
> > 5.16, but the regression has not been fixed yet.
> >
>
> Am I correct in thinging that this only happens with MGLRU?

Sorry about the confusion and let me clarify on this. The regression happens
on upstream Linux with the default page replacement mechanism.