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In-Reply-To: <20180829150136.GA10223@dhcp22.suse.cz>
From: Marinko Catovic <marinko.catovic@gmail.com>
Date: Wed, 29 Aug 2018 17:13:59 +0200
Message-ID: <CADF2uSoViODBbp4OFHTBhXvgjOVL8ft1UeeaCQjYHZM0A=p-dA@mail.gmail.com>
Subject: Re: Caching/buffers become useless after some time
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Sender: owner-linux-mm@kvack.org
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To: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>, Christopher Lameter <cl@linux.com>, linux-mm@kvack.org

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>
> trace data which starts _before_ the cache dropdown starts and while it
> is decreasing should be the first step. Ideally along with /proc/vmstat
> gathered at the same time. I am pretty sure you have some high order
> memory consumer which forces the reclaim and we over reclaim. Last data
> was not really conclusive as it didn't really captured the dropdown
> IIRC.
>

with before you mean in a totally healthy state?
as I can not tell when decreasing starts this would mean collecting data
over days perhaps. however, I have no issue with that.
As I do not want to miss anything that might help you, could you please
provide the commands for all the data you require?
one host is at a healthy state right now, I'd run that over there
immediately.

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<div dir=3D"ltr"><br><div class=3D"gmail_quote"><blockquote class=3D"gmail_=
quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1=
ex">
<br>
trace data which starts _before_ the cache dropdown starts and while it<br>
is decreasing should be the first step. Ideally along with /proc/vmstat<br>
gathered at the same time. I am pretty sure you have some high order<br>
memory consumer which forces the reclaim and we over reclaim. Last data<br>
was not really conclusive as it didn&#39;t really captured the dropdown<br>
IIRC.<br></blockquote><div><br></div><div>with before you mean in a totally=
 healthy state?</div><div>as I can not tell when decreasing starts this wou=
ld mean collecting data</div><div>over days perhaps. however, I have no iss=
ue with that.</div><div>As I do not want to miss anything that might help y=
ou, could you please</div><div>provide the commands for all the data you re=
quire?</div><div>one host is at a healthy state right now, I&#39;d run that=
 over there immediately.</div><div><br></div><div><br></div></div></div>

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