From: Michal Hocko <mhocko@kernel.org>
To: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
l.roehrs@profihost.ag, cgroups@vger.kernel.org,
Johannes Weiner <hannes@cmpxchg.org>,
Vlastimil Babka <vbabka@suse.cz>
Subject: Re: lot of MemAvailable but falling cache and raising PSI
Date: Tue, 10 Sep 2019 15:24:18 +0200 [thread overview]
Message-ID: <20190910132418.GC2063@dhcp22.suse.cz> (raw)
In-Reply-To: <b1fe902f-fce6-1aa9-f371-ceffdad85968@profihost.ag>
On Tue 10-09-19 15:14:45, Stefan Priebe - Profihost AG wrote:
> Am 10.09.19 um 15:05 schrieb Stefan Priebe - Profihost AG:
> >
> > Am 10.09.19 um 14:57 schrieb Michal Hocko:
> >> On Tue 10-09-19 14:45:37, Stefan Priebe - Profihost AG wrote:
> >>> Hello Michal,
> >>>
> >>> ok this might take a long time. Attached you'll find a graph from a
> >>> fresh boot what happens over time (here 17 August to 30 August). Memory
> >>> Usage decreases as well as cache but slowly and only over time and days.
> >>>
> >>> So it might take 2-3 weeks running Kernel 5.3 to see what happens.
> >>
> >> No problem. Just make sure to collect the requested data from the time
> >> you see the actual problem. Btw. you try my very dumb scriplets to get
> >> an idea of how much memory gets reclaimed due to THP.
> >
> > You mean your sed and sort on top of the trace file? No i did not with
> > the current 5.3 kernel do you think it will show anything interesting?
> > Which line shows me how much memory gets reclaimed due to THP?
Please re-read http://lkml.kernel.org/r/20190910082919.GL2063@dhcp22.suse.cz
Each command has a commented output. If you see nunmber of reclaimed
pages to be large for GFP_TRANSHUGE then you are seeing a similar
problem.
> Is something like a kernel memory leak possible? Or wouldn't this end up
> in having a lot of free memory which doesn't seem usable.
I would be really surprised if this was the case.
> I also wonder why a reclaim takes place when there is enough memory.
This is not clear yet and it might be a bug that has been fixed since
4.18. That's why we need to see whether the same is pattern is happening
with 5.3 as well.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-09-10 13:24 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-05 11:27 Stefan Priebe - Profihost AG
2019-09-05 11:40 ` Michal Hocko
2019-09-05 11:56 ` Stefan Priebe - Profihost AG
2019-09-05 16:28 ` Yang Shi
2019-09-05 17:26 ` Stefan Priebe - Profihost AG
2019-09-05 18:46 ` Yang Shi
2019-09-05 19:31 ` Stefan Priebe - Profihost AG
2019-09-06 10:08 ` Stefan Priebe - Profihost AG
2019-09-06 10:25 ` Vlastimil Babka
2019-09-06 18:52 ` Yang Shi
2019-09-07 7:32 ` Stefan Priebe - Profihost AG
2019-09-09 8:27 ` Michal Hocko
2019-09-09 8:54 ` Stefan Priebe - Profihost AG
2019-09-09 11:01 ` Michal Hocko
2019-09-09 12:08 ` Michal Hocko
2019-09-09 12:10 ` Stefan Priebe - Profihost AG
2019-09-09 12:28 ` Michal Hocko
2019-09-09 12:37 ` Stefan Priebe - Profihost AG
2019-09-09 12:49 ` Michal Hocko
2019-09-09 12:56 ` Stefan Priebe - Profihost AG
[not found] ` <52235eda-ffe2-721c-7ad7-575048e2d29d@profihost.ag>
2019-09-10 5:58 ` Stefan Priebe - Profihost AG
2019-09-10 8:29 ` Michal Hocko
2019-09-10 8:38 ` Stefan Priebe - Profihost AG
2019-09-10 9:02 ` Michal Hocko
2019-09-10 9:37 ` Stefan Priebe - Profihost AG
2019-09-10 11:07 ` Michal Hocko
2019-09-10 12:45 ` Stefan Priebe - Profihost AG
2019-09-10 12:57 ` Michal Hocko
2019-09-10 13:05 ` Stefan Priebe - Profihost AG
2019-09-10 13:14 ` Stefan Priebe - Profihost AG
2019-09-10 13:24 ` Michal Hocko [this message]
2019-09-11 6:12 ` Stefan Priebe - Profihost AG
2019-09-11 6:24 ` Stefan Priebe - Profihost AG
2019-09-11 13:59 ` Stefan Priebe - Profihost AG
2019-09-12 10:53 ` Stefan Priebe - Profihost AG
2019-09-12 11:06 ` Stefan Priebe - Profihost AG
2019-09-11 7:09 ` 5.3-rc-8 hung task in IO (was: Re: lot of MemAvailable but falling cache and raising PSI) Michal Hocko
2019-09-11 14:09 ` Stefan Priebe - Profihost AG
2019-09-11 14:56 ` Filipe Manana
2019-09-11 15:39 ` Stefan Priebe - Profihost AG
2019-09-11 15:56 ` Filipe Manana
2019-09-11 16:15 ` Stefan Priebe - Profihost AG
2019-09-11 16:19 ` Filipe Manana
2019-09-19 10:21 ` lot of MemAvailable but falling cache and raising PSI Stefan Priebe - Profihost AG
2019-09-23 12:08 ` Michal Hocko
2019-09-27 12:45 ` Vlastimil Babka
2019-09-30 6:56 ` Stefan Priebe - Profihost AG
2019-09-30 7:21 ` Vlastimil Babka
2019-10-22 7:41 ` Stefan Priebe - Profihost AG
2019-10-22 7:48 ` Vlastimil Babka
2019-10-22 10:02 ` Stefan Priebe - Profihost AG
2019-10-22 10:20 ` Oscar Salvador
2019-10-22 10:21 ` Vlastimil Babka
2019-10-22 11:08 ` Stefan Priebe - Profihost AG
2019-09-10 5:41 ` Stefan Priebe - Profihost AG
2019-09-09 11:49 ` Vlastimil Babka
2019-09-09 12:09 ` Stefan Priebe - Profihost AG
2019-09-09 12:21 ` Vlastimil Babka
2019-09-09 12:31 ` Stefan Priebe - Profihost AG
2019-09-05 12:15 ` Vlastimil Babka
2019-09-05 12:27 ` Stefan Priebe - Profihost AG
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