From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f41.google.com (mail-pj1-f41.google.com [209.85.216.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 22168149C7B for ; Wed, 27 May 2026 02:39:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.41 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779849561; cv=none; b=kbK6RW2ujnmYTv7D4sINAqnzLLmHlBFU0O4DLPVyuISBVVFYKO7iAiBy7k2qtpZQWI9WzpJwGjd4prh/qp0UFiVYL9wPF5RhTbaFHLVjpJ6Of14cer3mYSQ3yHo5bwT8/br3ewKnSP0Cg+U/ZHbpnpUufP5BIBBw6Md6nnL9Lkw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779849561; c=relaxed/simple; bh=YLHSJWtNRRKULvHiEhk/EuOJw3HGQnVcZ8LNPxAwLsM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=gdu1AOWNxMFVwT1ZF9ds9Cj2/hnem36RU03EenGiyWIHpGr2z6um43XD6DHFzZaUIV6K71jtPGa2pABRqwBKRtwtB15HQHEgLwPBUD1J+P1kLWgygDWtfFZ46N+OsJLHV16YRF6pYrH9H9y4Heg4yaGGuQXtkLCEptUUw4+WCt0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=ayI+kl0C; arc=none smtp.client-ip=209.85.216.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ayI+kl0C" Received: by mail-pj1-f41.google.com with SMTP id 98e67ed59e1d1-365d8e43759so5660196a91.0 for ; Tue, 26 May 2026 19:39:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1779849559; x=1780454359; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:from:to:cc:subject:date :message-id:reply-to; bh=sGwC6eNLghO2bBmS4gKEtdX6PelNtfsnZTEHkZ16hk4=; b=ayI+kl0CLKR5VSJ/Gf/s2mKDwbNBp9KiF4qPKCWfFUMVYKppunHFJqLVvNZHY18c19 FX3jelKC9mzQhdh5RsupERasj63J30hN/P9toP0ciMSWINYKJQ9USeGqdH8av5IIZifF 7Rpql11t9M9ZApGvsu1/WtmzrlOp/rkyx86pHSBAUhMLRkCcr7zYxxPHYflfXs4l8lNB i3DgcszCgaAq4ePyL8AvyFy/DCykRrmB6CC3eJ73lwJB5blQYd2wrQiUrWMHZOLoXXYa Dj46b3bJOhwtZKdh90zSRe0Na1qOUvi85/mokKjOvDfUkbpBnAgS8aidM8H5Cfppwxss ex3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779849559; x=1780454359; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=sGwC6eNLghO2bBmS4gKEtdX6PelNtfsnZTEHkZ16hk4=; b=kdguQ8BbnJ3EzK6lz5Qu/D+iNDotnRGsLqpvoZhLmjjdJynrrdncRrsQluw2SbqGVB dMtddJm4g8ALqsIs4M8TPgTlLggM0jUZO8QB4TISggpErFWbsv140jW5v1N9w2C10jT2 Lz6kol9yvVbpP04WPOunMoETHU8fwcyVnUQjex/pAGBrRgfHEMuuEhZx5f0alwxpKSnF 059xyuXIiSQbgINcjm8kv+BhAfk6eJ1kIVHp5F+Sa4/oATgVy7O4tk2WWQdXqfzDmCTs 438iRy5Hi0PUaKFlmNFnOWbKMkw2v0kO0+8zzfZPQazl9bpvA1ryGqaMhlqg1niJ0bMI xLzw== X-Forwarded-Encrypted: i=1; AFNElJ/PuUtHsGfQVCDSeTRLAh+MBn4/xFjO2+pzrAg/sW16CyQV6N63aa2JuH1h//T9v6cRqav9mgougcU=@vger.kernel.org X-Gm-Message-State: AOJu0YykqzihmPft3J+TozydCJTRxWBN3fS9q+DXlTysryGCTX95jtIi J5+ZRJuLQnhhNNbzd7Ly8s/bAd7QeiGYsMRY9FDrg/U++sZeLyGJe4Fj5TFYVA== X-Gm-Gg: Acq92OE2jWdYNSU41lmBHCaQYKR99kMYkzrudQoekVcI8YfKWXUsY+Y5gEVOA1nUUTs tqV0d48EP8W8iRaPOC+YZqyy3TInoAh94PQiLjpNQPCEm7nzeCWglLOnC1HF4XisvrDuLXwhyPG DViIOlsu6IAkOwx5WGyqJLO+cgf2k2fQFtYgyUhsGiPbJO2cyMUGS6rTWcSb/cxF7xBU1NZjHrT M/glB8KYMvS2i8XVp/1geeC1SzwXsmoaPVCoOZjDCMgCkG8hpjrg2ancrmScVK0ZlfZtcxiku5v w+WraVZ3UljWJZ84VbKuRt5ug+WChiq4nZe2cNqKvXosdf5FvfwZxAA09fRrVq366SiPduPXLrX /8P2GiaMpeGb77sCSqgbhyNrDxRWVESDeDE7yIHId29t9GJPutLLncLc07P0fzS+5FXELFNTtYJ 0a9LEFhtWw63Q8h3/8fOxav9HbzjZn7QkWfkMxhmJ9VJJ1w+0j056cdPo= X-Received: by 2002:a17:90a:ac10:b0:36a:5b56:5c1d with SMTP id 98e67ed59e1d1-36a5b565cf7mr12903624a91.11.1779849559393; Tue, 26 May 2026 19:39:19 -0700 (PDT) Received: from [10.125.192.130] ([210.184.73.204]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-c85202b946dsm11616672a12.13.2026.05.26.19.39.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 26 May 2026 19:39:18 -0700 (PDT) Message-ID: <8eea0a0d-615f-ff72-b019-0634a5f1028b@gmail.com> Date: Wed, 27 May 2026 10:39:08 +0800 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.15.0 Subject: Re: [PATCH v2 0/4] mm/zswap: Implement per-cgroup proactive writeback To: Yosry Ahmed Cc: Andrew Morton , tj@kernel.org, hannes@cmpxchg.org, shakeel.butt@linux.dev, mhocko@kernel.org, mkoutny@suse.com, nphamcs@gmail.com, chengming.zhou@linux.dev, muchun.song@linux.dev, roman.gushchin@linux.dev, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Hao Jia References: <20260525122242.36127-1-jiahao.kernel@gmail.com> <20260525122424.3b2818f06832d9d55da8d69b@linux-foundation.org> <9b2ac88c-a67f-2512-d898-3dadd50ec03e@gmail.com> From: Hao Jia In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2026/5/27 02:55, Yosry Ahmed wrote: > On Tue, May 26, 2026 at 4:56 AM Hao Jia wrote: >> >> >> >> On 2026/5/26 03:24, Andrew Morton wrote: >>> On Mon, 25 May 2026 20:22:38 +0800 Hao Jia wrote: >>> >>>> Zswap currently writes back pages to backing swap reactively, triggered >>>> either by the shrinker or by the pool reaching its size limit. Although >>>> proactive memory reclaim can automatically write back a portion of zswap >>>> pages via the shrinker, it cannot explicitly control the amount of >>>> writeback for a specific memory cgroup. Moreover, proactive memory reclaim >>>> may not always be triggered during a steady state. >>>> >>>> In certain scenarios, it is desirable to trigger writeback in advance to >>>> free up memory. For example, users may want to prepare for an upcoming >>>> memory-intensive workload by flushing cold memory to the backing storage >>>> when the system is relatively idle. >>>> >>>> This patch series introduces a "zswap_writeback_only" key to memory.reclaim >>>> cgroup interface, allowing users to proactively write back cold compressed >>>> pages from zswap to the backing swap device. When specified, this key >>>> bypasses standard memory reclaim and exclusively performs proactive zswap >>>> writeback up to the requested budget. If omitted, the default reclaim >>>> behavior remains unchanged. >>> >>> Thanks. AI review found a few things to complain about, one of them >>> described as "preexisting". >>> >> >> Thanks Andrew. I have replied to the AI's review comments in a separate >> email and posted v3. >> https://lore.kernel.org/all/20260526114601.67041-1-jiahao.kernel@gmail.com > > Generally speaking, please give time for reviewers to take a look > before sending a new version. Less than a day is usually too fast > (unless you're iterating super fast with the reviewers). Review > feedback does not have to be addressed immediately, usually wait for a > bit to collect as much feedback as possible before spinning a new > version. > Thanks for the advice, Yosry. Got it. > I will take a look at v3 soon, thank you. Appreciate you taking a look at v3. Thakns, Hao