From: Christian Brauner <christian@brauner.io>
To: Tim Murray <timmurray@google.com>
Cc: "Sultan Alsawaf" <sultan@kerneltoast.com>,
"Michal Hocko" <mhocko@kernel.org>,
"Suren Baghdasaryan" <surenb@google.com>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
"Arve Hjønnevåg" <arve@android.com>,
"Todd Kjos" <tkjos@android.com>,
"Martijn Coenen" <maco@android.com>,
"Joel Fernandes" <joel@joelfernandes.org>,
"Ingo Molnar" <mingo@redhat.com>,
"Peter Zijlstra" <peterz@infradead.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-drivers <devel@driverdev.osuosl.org>,
linux-mm <linux-mm@kvack.org>
Subject: Re: [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android
Date: Tue, 12 Mar 2019 19:50:56 +0100 [thread overview]
Message-ID: <CAHrFyr7wJsNAQ_NPAsBDA-g7useeetgJ-MBod40SQAmf08sXJw@mail.gmail.com> (raw)
In-Reply-To: <CAEe=Sx=MxzBB46WxuwHTQcocBkx1UW+fmVOa3VWv_eUferzVYw@mail.gmail.com>
On Tue, Mar 12, 2019 at 7:43 PM Tim Murray <timmurray@google.com> wrote:
>
> On Tue, Mar 12, 2019 at 10:45 AM Sultan Alsawaf <sultan@kerneltoast.com> wrote:
> >
> > On Tue, Mar 12, 2019 at 10:17:43AM -0700, Tim Murray wrote:
> > > Knowing whether a SIGKILL'd process has finished reclaiming is as far
> > > as I know not possible without something like procfds. That's where
> > > the 100ms timeout in lmkd comes in. lowmemorykiller and lmkd both
> > > attempt to wait up to 100ms for reclaim to finish by checking for the
> > > continued existence of the thread that received the SIGKILL, but this
> > > really means that they wait up to 100ms for the _thread_ to finish,
> > > which doesn't tell you anything about the memory used by that process.
> > > If those threads terminate early and lowmemorykiller/lmkd get a signal
> > > to kill again, then there may be two processes competing for CPU time
> > > to reclaim memory. That doesn't reclaim any faster and may be an
> > > unnecessary kill.
> > > ...
> > > - offer a way to wait for process termination so lmkd can tell when
> > > reclaim has finished and know when killing another process is
> > > appropriate
> >
> > Should be pretty easy with something like this:
>
> Yeah, that's in the spirit of what I was suggesting, but there are lot
> of edge cases around how to get that data out efficiently and PID
> reuse (it's a real issue--often the Android apps that are causing
> memory pressure are also constantly creating/destroying threads).
>
> I believe procfds or a similar mechanism will be a good solution to this.
Fwiw, I am working on this and have send a PR for inclusion in 5.1:
https://lore.kernel.org/lkml/20190312135245.27591-1-christian@brauner.io/
There's also a tree to track this work.
Christian
next prev parent reply other threads:[~2019-03-12 18:51 UTC|newest]
Thread overview: 113+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-10 20:34 [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android Sultan Alsawaf
2019-03-10 21:03 ` Greg Kroah-Hartman
2019-03-10 21:26 ` Sultan Alsawaf
2019-03-11 16:32 ` Joel Fernandes
2019-03-11 16:37 ` Joel Fernandes
2019-03-11 17:43 ` Michal Hocko
2019-03-11 17:58 ` Sultan Alsawaf
2019-03-11 20:10 ` Suren Baghdasaryan
2019-03-11 20:46 ` Sultan Alsawaf
2019-03-11 21:11 ` Joel Fernandes
2019-03-11 21:46 ` Sultan Alsawaf
2019-03-11 22:15 ` Suren Baghdasaryan
2019-03-11 22:36 ` Sultan Alsawaf
2019-03-12 8:05 ` Michal Hocko
2019-03-12 14:36 ` Suren Baghdasaryan
2019-03-12 15:25 ` Matthew Wilcox
2019-03-12 15:33 ` Michal Hocko
2019-03-12 15:39 ` Michal Hocko
2019-03-12 16:37 ` Sultan Alsawaf
2019-03-12 16:48 ` Michal Hocko
2019-03-12 16:58 ` Michal Hocko
2019-03-12 17:15 ` Suren Baghdasaryan
2019-03-12 17:17 ` Tim Murray
2019-03-12 17:45 ` Sultan Alsawaf
2019-03-12 18:43 ` Tim Murray
2019-03-12 18:50 ` Christian Brauner [this message]
2019-03-14 17:47 ` Joel Fernandes
2019-03-14 20:49 ` Sultan Alsawaf
2019-03-15 2:54 ` Joel Fernandes
2019-03-15 3:43 ` Sultan Alsawaf
2019-03-15 3:16 ` Steven Rostedt
2019-03-15 3:45 ` Sultan Alsawaf
2019-03-15 4:36 ` Daniel Colascione
2019-03-15 13:36 ` Joel Fernandes
2019-03-15 15:56 ` Suren Baghdasaryan
2019-03-15 16:12 ` Daniel Colascione
2019-03-15 16:43 ` Steven Rostedt
2019-03-15 17:17 ` Daniel Colascione
2019-03-15 18:03 ` Christian Brauner
2019-03-15 18:13 ` Joel Fernandes
2019-03-15 18:24 ` Christian Brauner
2019-03-15 18:49 ` Joel Fernandes
2019-03-16 17:31 ` Suren Baghdasaryan
2019-03-16 18:00 ` Daniel Colascione
2019-03-16 18:57 ` Christian Brauner
2019-03-16 19:37 ` Suren Baghdasaryan
2019-03-17 1:53 ` Joel Fernandes
2019-03-17 11:42 ` Christian Brauner
2019-03-17 15:40 ` Daniel Colascione
2019-03-18 0:29 ` Christian Brauner
2019-03-18 23:50 ` Joel Fernandes
2019-03-19 22:14 ` Christian Brauner
2019-03-19 22:26 ` Joel Fernandes
2019-03-19 22:48 ` Daniel Colascione
2019-03-19 23:10 ` Christian Brauner
2019-03-20 1:52 ` Joel Fernandes
2019-03-20 2:42 ` pidfd design Daniel Colascione
2019-03-20 3:59 ` Christian Brauner
2019-03-20 7:02 ` Daniel Colascione
2019-03-20 11:33 ` Joel Fernandes
2019-03-20 18:26 ` Christian Brauner
2019-03-20 18:38 ` Daniel Colascione
2019-03-20 18:51 ` Christian Brauner
2019-03-20 18:58 ` Andy Lutomirski
2019-03-20 19:14 ` Christian Brauner
2019-03-20 19:40 ` Daniel Colascione
2019-03-21 17:02 ` Andy Lutomirski
2019-03-25 20:13 ` Jann Horn
2019-03-25 20:23 ` Daniel Colascione
2019-03-25 23:42 ` Andy Lutomirski
2019-03-25 23:45 ` Christian Brauner
2019-03-26 0:00 ` Andy Lutomirski
2019-03-26 0:12 ` Christian Brauner
2019-03-26 0:24 ` Andy Lutomirski
2019-03-28 9:21 ` Christian Brauner
2019-03-20 19:19 ` Joel Fernandes
2019-03-20 19:29 ` Daniel Colascione
2019-03-24 14:44 ` Serge E. Hallyn
2019-03-24 18:48 ` Joel Fernandes
2019-03-20 19:11 ` Joel Fernandes
2019-05-07 2:16 ` [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android Sultan Alsawaf
2019-05-07 7:04 ` Greg Kroah-Hartman
2019-05-07 7:27 ` Sultan Alsawaf
2019-05-07 7:43 ` Greg Kroah-Hartman
2019-05-07 8:12 ` Sultan Alsawaf
2019-05-07 10:58 ` Christian Brauner
2019-05-07 16:28 ` Suren Baghdasaryan
2019-05-07 16:38 ` Christian Brauner
2019-05-07 16:53 ` Sultan Alsawaf
2019-05-07 20:01 ` Suren Baghdasaryan
2019-05-07 18:46 ` Joel Fernandes
2019-05-07 17:17 ` Sultan Alsawaf
2019-05-07 17:29 ` Greg Kroah-Hartman
2019-05-07 11:09 ` Greg Kroah-Hartman
2019-05-07 12:26 ` Michal Hocko
2019-05-07 15:31 ` Oleg Nesterov
2019-05-07 16:35 ` Sultan Alsawaf
2019-05-09 15:56 ` Oleg Nesterov
2019-05-09 18:33 ` Sultan Alsawaf
2019-05-10 15:10 ` Oleg Nesterov
2019-05-13 16:45 ` Sultan Alsawaf
2019-05-14 16:44 ` Steven Rostedt
2019-05-14 17:31 ` Sultan Alsawaf
2019-05-15 14:58 ` Oleg Nesterov
2019-05-15 17:27 ` Sultan Alsawaf
2019-05-15 18:32 ` Steven Rostedt
2019-05-15 18:52 ` Sultan Alsawaf
2019-05-15 20:09 ` Steven Rostedt
2019-05-16 13:54 ` Oleg Nesterov
2019-03-17 16:35 ` Serge E. Hallyn
2019-03-17 17:11 ` Daniel Colascione
2019-03-17 17:16 ` Serge E. Hallyn
2019-03-17 22:02 ` Suren Baghdasaryan
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