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Date:   Mon, 28 Oct 2019 11:56:17 -0400
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     Hillf Danton <hdanton@sina.com>
Cc:     linux-mm <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Matthew Wilcox <willy@infradead.org>,
        Michal Hocko <mhocko@suse.com>,
        Shakeel Butt <shakeelb@google.com>,
        Minchan Kim <minchan@kernel.org>, Mel Gorman <mgorman@suse.de>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Jan Kara <jack@suse.cz>
Subject: Re: [RFC v2] mm: add page preemption
Message-ID: <20191028155617.GA3156@cmpxchg.org>
References: <20191026112808.14268-1-hdanton@sina.com>
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On Sat, Oct 26, 2019 at 07:28:08PM +0800, Hillf Danton wrote:
> 
> The cpu preemption feature makes a task able to preempt other tasks
> of lower priorities for cpu. It has been around for a while.
> 
> This work introduces task prio into page reclaiming in order to add
> the page preemption feature that makes a task able to preempt other
> tasks of lower priorities for page.
> 
> No page will be reclaimed on behalf of tasks of lower priorities

... at which point they'll declare OOM and kill the high-pri task?

Please have a look at the cgroup2 memory.low control. This memory
prioritization problem has already been solved.