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From: Hillf Danton <hdanton@sina.com>
To: Axel Rasmussen <axelrasmussen@google.com>
Cc: chris@chrisdown.name,
	hannes@cmpxchg.org,
	linux-kernel@vger.kernel.org,
	linux-mm@kvack.org,
	yuzhao@google.com
Subject: Re: MGLRU premature memcg OOM on slow writes
Date: Fri,  1 Mar 2024 19:25:35 +0800
Message-Id: <20240301112535.1609-1-hdanton@sina.com>
In-Reply-To: <20240229235134.2447718-1-axelrasmussen@google.com>
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On Thu, 29 Feb 2024 15:51:33 -0800 Axel Rasmussen <axelrasmussen@google.com>
> 
> Yosry pointed out [1], where MGLRU used to call this but stopped doing that. It
> makes sense to me at least that doing writeback every time we age is too
> aggressive, but doing it in evict_folios() makes some sense to me, basically to
> copy the behavior the non-MGLRU path (shrink_inactive_list()) has.
> 
> I can send a patch which tries to implement this next week. In the meantime, Yu,

Better after working out why flusher failed to do the job, given background
writeback and balance_dirty_pages_ratelimited().
If pushing kswapd on the back makes any sense, what prevents you from pushing
flusher instead, given they are two different things by define?

> please let me know if what I've said here makes no sense for some reason. :)
> 
> [1]: https://lore.kernel.org/lkml/YzSiWq9UEER5LKup@google.com/