From: Andrew Morton <akpm@linux-foundation.org>
To: Vernon Yang <vernon2gm@gmail.com>
Cc: david@kernel.org, kasong@tencent.com, qi.zheng@linux.dev,
shakeel.butt@linux.dev, baohua@kernel.org,
axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com,
baoquan.he@linux.dev, hannes@cmpxchg.org, mhocko@kernel.org,
ljs@kernel.org, roman.gushchin@linux.dev, dave@stgolabs.net,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Vernon Yang <yanglincheng@kylinos.cn>,
stable@vger.kernel.org
Subject: Re: [PATCH] mm: vmscan: don't count per-node proactive reclaim as memory pressure
Date: Mon, 5 Oct 2026 05:54:02 -0700 [thread overview]
Message-ID: <20261005055402.61065464d9c66f1540a08c94@linux-foundation.org> (raw)
In-Reply-To: <cec875e1-2afc-44bf-929d-b8f2b2a795f8@gmail.com>
On Mon, 5 Oct 2026 18:10:45 +0800 Vernon Yang <vernon2gm@gmail.com> wrote:
> the phenomenon resembling
> > > senpai will appear again.
> >
> > What is this?
>
> This is commit e22c6ed90aa9, which addresses a scenario mentioned in
> memory limits of a cgroup, in detail as follows:
>
> Currently, this reclaim activity is accounted as memory pressure in the
> cgroup that the writer(!) belongs to. This is unexpected. It
> specifically causes problems for senpai
> (https://github.com/facebookincubator/senpai), which is an agent that
> routinely adjusts the memory limits and performs associated reclaim work
> in tens or even hundreds of cgroups running on the host. The cgroup that
> senpai is running in itself will report elevated levels of memory
> pressure, even though it itself is under no memory shortage or any sort of
> distress.
ah, thanks. It's arguably appropriate that the procfs-writing process
gets blamed for the I/O which it caused, but clearly that's the wrong
place to account the memory pressure.
prev parent reply other threads:[~2026-10-05 12:54 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-05 6:22 Vernon Yang
2026-10-05 6:30 ` Barry Song
2026-10-05 10:21 ` Vernon Yang
2026-10-06 10:17 ` Barry Song
2026-10-05 6:36 ` Andrew Morton
2026-10-05 10:10 ` Vernon Yang
2026-10-05 12:54 ` Andrew Morton [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20261005055402.61065464d9c66f1540a08c94@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=axelrasmussen@google.com \
--cc=baohua@kernel.org \
--cc=baoquan.he@linux.dev \
--cc=dave@stgolabs.net \
--cc=david@kernel.org \
--cc=hannes@cmpxchg.org \
--cc=kasong@tencent.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=ljs@kernel.org \
--cc=mhocko@kernel.org \
--cc=qi.zheng@linux.dev \
--cc=roman.gushchin@linux.dev \
--cc=shakeel.butt@linux.dev \
--cc=stable@vger.kernel.org \
--cc=vernon2gm@gmail.com \
--cc=weixugc@google.com \
--cc=yanglincheng@kylinos.cn \
--cc=yuanchu@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®