Re: MGLRU premature memcg OOM on slow writes

[Hillf Danton]

On Tue, 12 Mar 2024 17:08:22 -0400 Johannes Weiner <hannes@xxxxxxxxxxx>
> 
> Back to the broader question though: if reclaim demand outstrips clean
> pages and the only viable candidates are dirty ones (e.g. an
> allocation spike in the presence of dirty/writeback pages), there only
> seem to be 3 options:
> 
> 1) sleep-wait for writeback
> 2) continue scanning, aka busy-wait for writeback + age inversions
> 3) find nothing and declare OOM

  4) make dirty ratio match your writeback bandwidth [1]

[1] Subject: Re: 4.8.8 kernel trigger OOM killer repeatedly when I have lots of RAM that should be free
https://lore.kernel.org/lkml/CA+55aFzNe=3e=cDig+vEzZS5jm2c6apPV4s5NKG4eYL4_jxQjQ@xxxxxxxxxxxxxx/