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From: Costa Alexoglou <costa@dbtune.com>
Date: Mon, 4 Nov 2024 14:35:23 +0100
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Subject: Re: Used memory calculation in containers - docker stats and file cache
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> I don't know if Docker does anything strange here.

I am not sure if this is docker specific or cgroup comes into play.
The measurement is implemented in docker CLI, but I would make the
assumption
that the eviction is done within the cgroup scope.

> A large file (or many smaller files) which is cached is deleted

The increase pattern is "incremental" until the huge eviction, and this is
my question.
Couldn't also the eviction happen incrementally rather than 15GB of file
cache evicted on an instant?

> So I'd double check the logs if there are
any errors.

Not any error in the logs, unfortunately (or fortunately).


Seems like this issue <https://github.com/hashicorp/nomad/issues/16230>, or
the parent one <https://github.com/moby/moby/issues/10824> that everyone is
linking to this.

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<div dir=3D"ltr">&gt; I don&#39;t know if Docker does anything strange here=
.<div><br></div><div>I am not sure if this is docker specific or cgroup com=
es into play.=C2=A0</div><div>The measurement is implemented in docker CLI,=
 but I would make the assumption</div><div>that the eviction is done within=
 the cgroup scope.</div><div><br></div><div>&gt; A large file (or many smal=
ler files) which is cached is deleted</div><div><br></div><div>The increase=
 pattern is &quot;incremental&quot; until the huge eviction, and this is my=
 question.</div><div>Couldn&#39;t also the eviction happen incrementally ra=
ther than 15GB of file cache evicted on an instant?</div><div><br></div><di=
v>&gt; So I&#39;d double check the logs if there are</div>any errors.<br><b=
r>Not any error in the=C2=A0logs, unfortunately=C2=A0(or fortunately).<div>=
<br></div><div><br></div><div>Seems like <a href=3D"https://github.com/hash=
icorp/nomad/issues/16230">this issue</a>, or the <a href=3D"https://github.=
com/moby/moby/issues/10824">parent one</a>=C2=A0that everyone is linking to=
 this.</div></div>

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