From: Johannes Weiner <hannes@cmpxchg.org>
To: Youngjun Park <youngjun.park@lge.com>
Cc: akpm@linux-foundation.org, chrisl@kernel.org, linux-mm@kvack.org,
cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
kasong@tencent.com, mhocko@kernel.org, roman.gushchin@linux.dev,
shakeel.butt@linux.dev, muchun.song@linux.dev,
shikemeng@huaweicloud.com, baoquan.he@linux.dev,
baohua@kernel.org, yosry@kernel.org, joshua.hahnjy@gmail.com,
taejoon.song@lge.com, her0gyugyu@gmail.com, lianux.mm@gmail.com
Subject: Re: [RFC PATCH v11 0/4] mm/swap: priority-based swap tiers with per-cgroup selection
Date: Wed, 16 Sep 2026 16:04:34 -0400 [thread overview]
Message-ID: <20260916200434.GA5784@cmpxchg.org> (raw)
In-Reply-To: <20260916183437.2946306-1-youngjun.park@lge.com>
On Thu, Sep 17, 2026 at 03:34:33AM +0900, Youngjun Park wrote:
> Per-cgroup swap in debugfs
> ==========================
>
> Patches 3 and 4 let a memory cgroup choose its tiers through debugfs.
>
> # swapon -p 100 /dev/nvme0n1p2
> # swapon -p 50 /dev/sdb2
> # cat /sys/kernel/debug/swap/tiers
> Idx Prio
> 0 100
> 1 50
> # echo "/batch 0x2" > /sys/kernel/debug/swap/memcg_tiers
>
> Bit i of the mask is tier i, so /batch swaps only to sdb2. A tier keeps
> its index for its lifetime, so the mask keeps selecting the same tier
> across swapon and swapoff.
Can the cgroup be given a priority limit? That would have pretty
obvious inheritance semantics:
root
`- batch (memory.swap.prio.max = 20)
`- task (memory.swap.prio.max = max)
`- logs (memory.swap.prio.max = 10)
`- interactive (memory.swap.prio.max = max)
`- task (memory.swap.prio.max)
next prev parent reply other threads:[~2026-09-16 20:04 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-16 18:34 [RFC PATCH v11 0/4] mm/swap: priority-based swap tiers with per-cgroup selection Youngjun Park
2026-09-16 18:34 ` [RFC PATCH v11 1/4] mm: swap: introduce swap tier infrastructure Youngjun Park
2026-09-16 18:34 ` [RFC PATCH v11 2/4] mm: swap: allocate swap slots from swap tiers Youngjun Park
2026-09-16 18:34 ` [RFC PATCH v11 3/4] mm: swap: add a debugfs interface for memcg tier selection Youngjun Park
2026-09-16 18:34 ` [RFC PATCH v11 4/4] mm: swap: filter swap allocation by memcg tier mask Youngjun Park
2026-09-16 20:04 ` Johannes Weiner [this message]
2026-09-20 16:20 ` [RFC PATCH v11 0/4] mm/swap: priority-based swap tiers with per-cgroup selection Youngjun Park
2026-09-23 17:15 ` Johannes Weiner
2026-09-25 6:54 ` Lian Wang
2026-09-26 15:49 ` Youngjun Park
2026-09-26 15:41 ` Youngjun Park
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=20260916200434.GA5784@cmpxchg.org \
--to=hannes@cmpxchg.org \
--cc=akpm@linux-foundation.org \
--cc=baohua@kernel.org \
--cc=baoquan.he@linux.dev \
--cc=cgroups@vger.kernel.org \
--cc=chrisl@kernel.org \
--cc=her0gyugyu@gmail.com \
--cc=joshua.hahnjy@gmail.com \
--cc=kasong@tencent.com \
--cc=lianux.mm@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=muchun.song@linux.dev \
--cc=roman.gushchin@linux.dev \
--cc=shakeel.butt@linux.dev \
--cc=shikemeng@huaweicloud.com \
--cc=taejoon.song@lge.com \
--cc=yosry@kernel.org \
--cc=youngjun.park@lge.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.