From: Michal Hocko <mhocko@kernel.org>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Suren Baghdasaryan <surenb@google.com>,
Vlastimil Babka <vbabka@suse.cz>,
"Artem S. Tashkinov" <aros@gmx.com>,
LKML <linux-kernel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>
Subject: Re: Let's talk about the elephant in the room - the Linux kernel's inability to gracefully handle low memory pressure
Date: Wed, 7 Aug 2019 09:59:27 +0200 [thread overview]
Message-ID: <20190807075927.GO11812@dhcp22.suse.cz> (raw)
In-Reply-To: <20190806220150.GA22516@cmpxchg.org>
On Tue 06-08-19 18:01:50, Johannes Weiner wrote:
> On Tue, Aug 06, 2019 at 09:27:05AM -0700, Suren Baghdasaryan wrote:
[...]
> > > > I'm not sure 10s is the perfect value here, but I do think the kernel
> > > > should try to get out of such a state, where interacting with the
> > > > system is impossible, within a reasonable amount of time.
> > > >
> > > > It could be a little too short for non-interactive number-crunching
> > > > systems...
> > >
> > > Would it be possible to have a module with tunning knobs as parameters
> > > and hook into the PSI infrastructure? People can play with the setting
> > > to their need, we wouldn't really have think about the user visible API
> > > for the tuning and this could be easily adopted as an opt-in mechanism
> > > without a risk of regressions.
>
> It's relatively easy to trigger a livelock that disables the entire
> system for good, as a regular user. It's a little weird to make the
> bug fix for that an opt-in with an extensive configuration interface.
Yes, I definitely do agree that this is a bug fix more than a
feature. The thing is that we do not know what the proper default is for
a wide variety of workloads so some way of configurability is needed
(level and period). If making this a module would require a lot of
additional code then we need a kernel command line parameter at least.
A module would have a nice advantage that you can change your
configuration without rebooting. The same can be achieved by a sysfs on
the other hand.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-08-07 7:59 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-04 9:23 Let's talk about the elephant in the room - the Linux kernel's inability to gracefully handle low memory pressure Artem S. Tashkinov
2019-08-05 12:13 ` Vlastimil Babka
2019-08-05 13:31 ` Michal Hocko
2019-08-05 16:47 ` Suren Baghdasaryan
2019-08-05 18:55 ` Johannes Weiner
2019-08-06 9:29 ` Michal Hocko
2019-08-05 19:31 ` Johannes Weiner
2019-08-06 1:08 ` Suren Baghdasaryan
2019-08-06 9:36 ` Vlastimil Babka
2019-08-06 14:27 ` Johannes Weiner
2019-08-06 14:36 ` Michal Hocko
2019-08-06 16:27 ` Suren Baghdasaryan
2019-08-06 22:01 ` Johannes Weiner
2019-08-07 7:59 ` Michal Hocko [this message]
2019-08-07 20:51 ` Johannes Weiner
2019-08-07 21:01 ` Andrew Morton
2019-08-07 21:34 ` Johannes Weiner
2019-08-07 21:12 ` Johannes Weiner
2019-08-08 11:48 ` Michal Hocko
2019-08-08 15:10 ` ndrw.xf
2019-08-08 16:32 ` Michal Hocko
2019-08-08 17:57 ` ndrw.xf
2019-08-08 18:59 ` Michal Hocko
2019-08-08 21:59 ` ndrw
2019-08-09 8:57 ` Michal Hocko
2019-08-09 10:09 ` ndrw
2019-08-09 10:50 ` Michal Hocko
2019-08-09 14:18 ` Pintu Agarwal
2019-08-10 12:34 ` ndrw
2019-08-12 8:24 ` Michal Hocko
2019-08-10 21:07 ` ndrw
2021-07-24 17:32 ` Alexey Avramov
2019-08-08 14:47 ` Vlastimil Babka
2019-08-08 17:27 ` Johannes Weiner
2019-08-09 14:56 ` Vlastimil Babka
2019-08-09 17:31 ` Johannes Weiner
2019-08-13 13:47 ` Vlastimil Babka
2019-08-06 21:43 ` James Courtier-Dutton
2019-08-06 19:00 ` Florian Weimer
2019-08-20 6:46 ` Daniel Drake
2019-08-21 21:42 ` James Courtier-Dutton
2019-08-29 12:29 ` Michal Hocko
2019-09-02 20:15 ` Pavel Machek
2019-08-23 1:54 ` ndrw
2019-08-23 2:14 ` Daniel Drake
[not found] <20190805090514.5992-1-hdanton@sina.com>
2019-08-05 12:01 ` Artem S. Tashkinov
2019-08-06 8:57 Johannes Buchner
2019-08-06 19:43 Remi Gauvin
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