From: Johannes Weiner <hannes@cmpxchg.org>
To: "Gregory Price (Meta)" <gourry@gourry.net>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
kernel-team@meta.com, akpm@linux-foundation.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,
baolin.wang@linux.alibaba.com, david@kernel.org,
mhocko@kernel.org, ljs@kernel.org, dave@stgolabs.net,
roman.gushchin@linux.dev, stable@vger.kernel.org
Subject: Re: [PATCH] mm/vmscan: reclaim every zone in per-node proactive reclaim
Date: Mon, 19 Oct 2026 22:16:45 +0200 [thread overview]
Message-ID: <20261019201645.GK371161@cmpxchg.org> (raw)
In-Reply-To: <20261019185002.3428594-1-gourry@gourry.net>
On Mon, Oct 19, 2026 at 02:50:02PM -0400, Gregory Price (Meta) wrote:
> user_proactive_reclaim() limits per-node reclaim to
> gfp_zone(GFP_KERNEL), which is ZONE_NORMAL. Proactive reclaim serves no
> allocation, but that limit makes shrink_node() skip every ZONE_MOVABLE
> folio, so writing to /sys/devices/system/node/nodeN/reclaim never
> reclaims a node's movable memory. A movable-only node, such as dax/kmem
> or hotplugged memory onlined movable, reclaims nothing and fails with
> -EAGAIN.
>
> To reproduce, fill a movable-only node with clean page cache and write
> 200M to its nodeN/reclaim: the write fails with -EAGAIN and the page
> cache stays. The same write to a ZONE_NORMAL node frees 200MB.
>
> Scan every zone, as memory.reclaim does.
>
> Fixes: b980077899ea4 ("mm: introduce per-node proactive reclaim interface")
> Cc: stable@vger.kernel.org
> Signed-off-by: Gregory Price (Meta) <gourry@gourry.net>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
next prev parent reply other threads:[~2026-10-19 20:16 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-19 18:50 [PATCH] mm/vmscan: reclaim every zone in per-node proactive reclaim Gregory Price (Meta)
2026-10-19 20:14 ` Barry Song
2026-10-19 20:16 ` Johannes Weiner [this message]
2026-10-19 20:51 ` Harry Yoo
2026-10-19 22:06 ` Shakeel Butt
2026-10-19 22:52 ` Yosry Ahmed
2026-10-20 0:36 ` SJ Park
2026-10-20 1:49 ` Balbir Singh
2026-10-20 3:04 ` Gregory Price
2026-10-20 7:49 ` Michal Hocko
2026-10-20 15:19 ` Kunwu Chan
2026-10-20 16:59 ` Davidlohr Bueso
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=20261019201645.GK371161@cmpxchg.org \
--to=hannes@cmpxchg.org \
--cc=akpm@linux-foundation.org \
--cc=axelrasmussen@google.com \
--cc=baohua@kernel.org \
--cc=baolin.wang@linux.alibaba.com \
--cc=baoquan.he@linux.dev \
--cc=dave@stgolabs.net \
--cc=david@kernel.org \
--cc=gourry@gourry.net \
--cc=kasong@tencent.com \
--cc=kernel-team@meta.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=weixugc@google.com \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.