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Tashkinov" , Andrew Morton , LKML , linux-mm Subject: Re: Let's talk about the elephant in the room - the Linux kernel's inability to gracefully handle low memory pressure Message-ID: <20190807211245.GA11071@cmpxchg.org> References: <20190805193148.GB4128@cmpxchg.org> <398f31f3-0353-da0c-fc54-643687bb4774@suse.cz> <20190806142728.GA12107@cmpxchg.org> <20190806143608.GE11812@dhcp22.suse.cz> <20190806220150.GA22516@cmpxchg.org> <20190807075927.GO11812@dhcp22.suse.cz> <20190807205138.GA24222@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190807205138.GA24222@cmpxchg.org> User-Agent: Mutt/1.12.0 (2019-05-25) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Aug 07, 2019 at 04:51:42PM -0400, Johannes Weiner wrote: > Per default, the OOM killer will engage after 15 seconds of at least > 80% memory pressure. These values are tunable via sysctls > vm.thrashing_oom_period and vm.thrashing_oom_level. Let's go with this: Per default, the OOM killer will engage after 15 seconds of at least 80% memory pressure. From experience, at 80% the user is experiencing multi-second reaction times. 15 seconds is chosen to be long enough to not OOM kill a short-lived spike that might resolve itself, yet short enough for users to not press the reset button just yet.