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Date:   Mon, 11 Mar 2019 17:11:25 -0400
From:   Joel Fernandes <joel@joelfernandes.org>
To:     Sultan Alsawaf <sultan@kerneltoast.com>
Cc:     Suren Baghdasaryan <surenb@google.com>,
        Michal Hocko <mhocko@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arve =?iso-8859-1?B?SGr4bm5lduVn?= <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Christian Brauner <christian@brauner.io>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>, devel@driverdev.osuosl.org,
        linux-mm <linux-mm@kvack.org>, Tim Murray <timmurray@google.com>
Subject: Re: [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android
Message-ID: <20190311211125.GA127617@google.com>
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On Mon, Mar 11, 2019 at 01:46:26PM -0700, Sultan Alsawaf wrote:
> On Mon, Mar 11, 2019 at 01:10:36PM -0700, Suren Baghdasaryan wrote:
> > The idea seems interesting although I need to think about this a bit
> > more. Killing processes based on failed page allocation might backfire
> > during transient spikes in memory usage.
> 
> This issue could be alleviated if tasks could be killed and have their pages
> reaped faster.

But the point is that a transient temporary memory spike should not be a
signal to kill _any_ process.  The reaction to kill shouldn't be so
spontaneous that unwanted tasks are killed because the system went into
panic mode. It should be averaged out which I believe is what PSI does.

thanks,

- Joel