From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6DB8C4167B for ; Fri, 15 Dec 2023 09:40:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 45C0D6B03FD; Fri, 15 Dec 2023 04:40:51 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 2D2886B03F7; Fri, 15 Dec 2023 04:40:51 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0DCD16B03E1; Fri, 15 Dec 2023 04:40:51 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id DA6BD6B03D0 for ; Fri, 15 Dec 2023 04:40:50 -0500 (EST) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id B3133140357 for ; Fri, 15 Dec 2023 09:40:50 +0000 (UTC) X-FDA: 81568558260.27.37942A4 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf01.hostedemail.com (Postfix) with ESMTP id 8EEC540006 for ; Fri, 15 Dec 2023 09:40:47 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=KHhvqwen; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf01.hostedemail.com: domain of chrisl@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=chrisl@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1702633247; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=B1jVCgUdR0dEGHelPgDtGvwgu8YigQ5hzfeCXGXgKnY=; b=OET7SUuCSo4+BMAESZKftpjMh7l7XTJB8VHi7wl5OHmI52YgEldyBDWPp+METypbunZA6H SHf14+ABg93Ijag0oVsitdeMQve2hYD63b7d/BtyfwhkZKDT1c9Q5Tp3wJDJ/A+HflimeL Lz3KeaHjYMB4wjsvqeNNqISOpD04LKU= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=KHhvqwen; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf01.hostedemail.com: domain of chrisl@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=chrisl@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1702633247; a=rsa-sha256; cv=none; b=1FN5F1CQ0G9tLRrrC+WNP1WDfVt0kshIOVdyTpDS46SRa3UeEat44DFPrEBeb7jpQStU+a +Xc6RqDmHG8NEF8rShzw2f8NGvs6MVx12pZ35LQNM2H/7G8Z1rK8q8BLwYk70C1XkqA8Ww o01yR2QeW5sgD50qu2qcxDnbWet7Uq0= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A5B4162512 for ; Fri, 15 Dec 2023 09:40:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5849EC433C7 for ; Fri, 15 Dec 2023 09:40:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1702633246; bh=vVpmxdeUmcOhDj8UvS9uojHcu7m53pDfJgItKw2MeOo=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=KHhvqwen/RLPuNr7ABccWxNkon+Qc3eIA3eWWTIFEDdt+p4s2TPl5UehB1jzPvSkt LvAxBBuSG7gBt3IL73uYGw/lazeTUyF7xBBKdyH+WiXu+hS2JCqdEHQSoUoAEcx6Gq qub5vDlyMwDe65hSDU60v6RIVUdSXcVrfTaXhF8UlGmcomUR/lGIaChWuCqxkIjx5N hgjoRpbC32IvMjdmQKOZGnqDHygLrDridtpPDAkTjgGwVG8mMrCpTmZLqalC1QjtIY lS11o6sQqNkFA4REuMVYMvNC8bZix0+nzd4+sMwgTFp/HOqmMVmzc1SJGdJnaypePY Ju3gWJ66qpEXQ== Received: by mail-pf1-f171.google.com with SMTP id d2e1a72fcca58-6cea0fd9b53so190089b3a.1 for ; Fri, 15 Dec 2023 01:40:46 -0800 (PST) X-Gm-Message-State: AOJu0YwRgNkdWjQ1ql8mQQtbyq4n05KSV+eLSxj/X7QKqxE41oCpknju Ah4NmhNvEq43kr+3HriPDalmxC2Zo86pT5TS5ULYag== X-Google-Smtp-Source: AGHT+IGFpMfw5GVwdU1bv9gHE5DcEHMKFKSN1w+PyKECjS7he1nzY4esromMqlEbNOSnmh4B2nwnj3VlCNgz8AtqcNk= X-Received: by 2002:a05:6a20:77a9:b0:18f:97c:8256 with SMTP id c41-20020a056a2077a900b0018f097c8256mr5200831pzg.96.1702633224789; Fri, 15 Dec 2023 01:40:24 -0800 (PST) MIME-Version: 1.0 References: <20231207192406.3809579-1-nphamcs@gmail.com> <20231209034229.GA1001962@cmpxchg.org> <20231214171137.GA261942@cmpxchg.org> In-Reply-To: From: Chris Li Date: Fri, 15 Dec 2023 01:40:12 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v6] zswap: memcontrol: implement zswap writeback disabling To: Fabian Deutsch Cc: Yu Zhao , Johannes Weiner , Minchan Kim , Nhat Pham , "akpm@linux-foundation.org" , "tj@kernel.org" , "lizefan.x@bytedance.com" , "cerasuolodomenico@gmail.com" , "yosryahmed@google.com" , "sjenning@redhat.com" , "ddstreet@ieee.org" , "vitaly.wool@konsulko.com" , "mhocko@kernel.org" , "roman.gushchin@linux.dev" , "shakeelb@google.com" , "muchun.song@linux.dev" , "hughd@google.com" , "corbet@lwn.net" , "konrad.wilk@oracle.com" , "senozhatsky@chromium.org" , "rppt@kernel.org" , "linux-mm@kvack.org" , "kernel-team@meta.com" , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , "david@ixit.cz" , Kairui Song , Zhongkun He Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 8EEC540006 X-Stat-Signature: sgzj5mq56d7k75uhnzggwx7uskgu7umu X-Rspam-User: X-HE-Tag: 1702633247-47315 X-HE-Meta: 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 z9mbljkz af9pEQ6CB34GtBd1TpbyCdsINv5KLn+rhxTyMX1jo4pIS1msj3cFbEs7oQXaajq44v1JdRgk+GbLqVFonq+WmB+nOBm3za/7m0MtyrxZNB20H7EbE4VYm7zow/JZDRccGnf6qwU8p9/HnWe2dwnfk6GmF96Tt1Y6Ng6R8Qg/cc/18qPDwWKd8JJ38juNFP4XB2IlsVHH8n7uFiRRvleWdUjHGywGFz3h7Mj/Vf0UDr3j1isV8Vvw93RN4AcxOoCSAEaCG3ZXTqX54vagWsjxmiFTtNMA7JuTfGL9D 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: On Thu, Dec 14, 2023 at 11:42=E2=80=AFPM Fabian Deutsch wrote:. > > > > Just to clarify, the "node" you mean the "node" in kubernetes sense, > > which is the whole machine. In the Linux kernel MM context, the node > > often refers to the NUMA memory node, that is not what you mean here, > > right? > > Correct, I was referring to a kubernetes node, not numa node. > > > > >> - With todays node level swap, and setting memory.swap.max=3D0 for all= cgroups allows you toachieve a similar behavior (only opt-in cgroups will = get swap). > >> - the above approach however will still have a shared swap backend for= all cgroups. > > > > Yes, the "memory.swap.tires" idea is trying to allow cgroups to select > > a subset of the swap backend in a specific order. It is still in the > > early stage of discussion. If you have any suggestion or feedback in > > that direction, I am looking forward to hearing that. > > Interesting. There have been concerns to leak confidential data accidenta= lly when it's getting written to a swap device. One common solution is to encrypt the data written to the device. If someone gets hold of the swapped outed device without the key, they can't get to the memory data without the key. > The other less discussed item was QoS for swap io traffic. > > At a first glance it seems like tires could help with the second use-case= . The idea is that you can select the swap tiers list for each cgroup. That way you can assign different swap QoS to different cgroup. Chris