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h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=Evpm/Xp4HEawLAca2Dr/IYrDMUB6TJgwKEN2KGZtkv5l5V9MiTi6M4pCKxW9jQQl4 EXCps9O10FaZi5iogL4zwAwyGuqKtWw2RWfIoZ+ykZUbM9BmdVzthIb64ZTZ178SQP lvKdh/TUN/vEb9tSpKbQpyIZaKDQyWu5Vsvwer1yrRUg2kcebYsO++Cmg+Un3GvPL1 sYBvOilDGMOtG7Ua40/+KK5fWkooPI4hwNlK+TsmdkJ//TJstgvF9B9WpZ1s5RPTRq 8f77T8+y8v8sD4o06mFGLivACtUH29lIJJ7/4r1w+W1R4f+engrHxyfqHfDcBQPDkh omvz535JgyZXQ== Received: by mail-yw1-f182.google.com with SMTP id 00721157ae682-7963a209b97so28965787b3.2 for ; Wed, 11 Feb 2026 22:12:17 -0800 (PST) X-Forwarded-Encrypted: i=1; AJvYcCVI9r0UqfO0Miq1GYtjFaYQq+PmlW9X0zmkw1NO8qJvHJpq8uLpr5ldhTZ8G+IMPbGz867mJ71F8g==@kvack.org X-Gm-Message-State: AOJu0YxjD4Q7E1P/2cY4aJZCo1gO3sbdh6wQmRERL5IH3DND5LJgEx2+ wFQeV/YCwRURh8zGc6O4/PDwmWCosJfo4P1/h36k0wup9QEQAceCn7L8HksXmsDyPd4UMttIubT XPdG+gsqN2NVmvxpfsOsb4jh7tly5A2eY8Wq0DsR0Tw== X-Received: by 2002:a05:690c:c50e:b0:796:3124:6544 with SMTP id 00721157ae682-797930a055fmr18331997b3.3.1770876736713; Wed, 11 Feb 2026 22:12:16 -0800 (PST) MIME-Version: 1.0 References: <20260126065242.1221862-1-youngjun.park@lge.com> In-Reply-To: <20260126065242.1221862-1-youngjun.park@lge.com> From: Chris Li Date: Wed, 11 Feb 2026 22:12:04 -0800 X-Gmail-Original-Message-ID: X-Gm-Features: AZwV_QjzITKiyww4DWMCdNMAPZSzThNC5YyMlw-tK6Rc3bhA13w9hO026qLdfDQ Message-ID: Subject: Re: [RFC PATCH v2 0/5] mm/swap, memcg: Introduce swap tiers for cgroup based swap control To: Youngjun Park Cc: Andrew Morton , linux-mm@kvack.org, Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , gunho.lee@lge.com, taejoon.song@lge.com, austin.kim@lge.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 9CC53100003 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: j8gwsxi9dgonk4oa5jtmf7ipqxccxycx X-HE-Tag: 1770876738-264564 X-HE-Meta: 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 6cxSPqxR iCXg0/ISwGDrOmZNGzbPmFPPxSsJSwaAE/bHJJSWfJWpsVH6/AQKPEzbUtrPzWRyUUbZjYgQuo4gveais9NuDykrxoacFuiHChMrjm4hDehjFsflryUgcFcrtgKgKJ5QMhSj4XqrHhZobI+qLbXBId+PFiAtxOr/nHy0Ltnz8Nu9AtmYAARrN66IF8Sm9+TfbXona+53PGa02z5QI/kcoN+UknJFQpXM6rW9EI1Zv7nko6jw1sASfYBpLN0oEYkKXHGmOA0f+uEEJuTF5mINVHkzyUBcAl6CzyEutgGh0SNYnB7G/AJWXdSDuJQZA/4E6co+GQXTToN8MI3I= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Youngjun, On Sun, Jan 25, 2026 at 10:53=E2=80=AFPM Youngjun Park wrote: > > This is the second version of the RFC for the "Swap Tiers" concept. > Link to v1: https://lore.kernel.org/linux-mm/20251109124947.1101520-1-you= ngjun.park@lge.com/ > > This version incorporates feedback received during LPC 2025 and addresses > comments from the previous review. We have also included experimental > results based on usage scenarios intended for our internal platforms. Thanks for the patches series. Sorry for the late reply. I have been wanting to reply to it but get super busy at work. Some high level feedback for the series. Now that you demonstrated the whole series, let's focus on making small mergiable baby steps. Just like the swap table has different phases. Make each step minimal, each step shows some value. Do the MVP, we can always add more features as a follow up step. I suggest the first step is getting the tiers bits defined. Add only, no delete. Get that reviewed and merged, then the next step is to use those tiers. Chris