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 355ABC4167B for ; Mon, 27 Nov 2023 07:42:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 992816B0303; Mon, 27 Nov 2023 02:42:31 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 942746B0304; Mon, 27 Nov 2023 02:42:31 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 80A5E6B0305; Mon, 27 Nov 2023 02:42:31 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 719776B0303 for ; Mon, 27 Nov 2023 02:42:31 -0500 (EST) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 3D22716012E for ; Mon, 27 Nov 2023 07:42:31 +0000 (UTC) X-FDA: 81502941702.04.A38A93E Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf24.hostedemail.com (Postfix) with ESMTP id 76AA218000D for ; Mon, 27 Nov 2023 07:42:28 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=HnwmaykA; spf=pass (imf24.hostedemail.com: domain of chrisl@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=chrisl@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1701070949; 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=rROM1MAuP2epaHhX6fHHDfXixafW+fcvrWkBOWzK1wc=; b=XpYIJ5C4mfIGznuSC8AC/Ugy+8VzNZE5i3Uhw40xlo6IWEUFCqGnJSQYErFFwsO+5uQzJM Jlt/CCMjFUxiV6opjGtVQy0vey6qhcNuAMH3mS/kwFBszuZ8fZOJ4zL6NI5OwXKhmZY5Iw T8ES5NwsMoNYLqkzh8+xOfeWzs+5ACs= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1701070949; a=rsa-sha256; cv=none; b=ksE314LWOTENWUc2Mea5C/TBGKDf4yJ3hAQo1t+A0UpKvns8vY/cgxmjM7wKz83p8BROt8 KKWHsnx74qlwRjRVAG2os3mZNwKCtqY6jEoFDZstwQbyvoMPQcSYwrMjfw/b9NrCwANdaZ cAP71Zin6ssotu8UPYZFhNTaZdxUz8I= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=HnwmaykA; spf=pass (imf24.hostedemail.com: domain of chrisl@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=chrisl@kernel.org; dmarc=pass (policy=none) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 60FB0CE0934 for ; Mon, 27 Nov 2023 07:42:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A93BC433CD for ; Mon, 27 Nov 2023 07:42:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701070943; bh=8FsHT2Xzon2e0xd3rsRca6eGh3KS8yCnz1RZFCNvPxY=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=HnwmaykAFhH00oP/GM9Lhke7OaPq5UUVWk9tlQwSfzs+nHHyRtlfrXjSQv9uYGwuh eb3VPBICH22rStDvM35PrzQbCR8/iraKKRkd9sJd1NGxFal+cOtLfN+b+j2WvEEwtA asuaysndIrxQXXz4DNqydexnUKEOkwnrhQJZWajm8dca0o6WCL/bmsKTa0Fs+gLXCW 6hTAkCE5BIi66HIeyGjXirTVBy+QXd3ttn/Lybb+mN34XcbzA+fLLgk115J1VYL3lw ECAvE793NRSTl2ba4zG9UfVciI82s5P9Y9PrKTwIArS6h23S8Ff/R8fZiYs9DNBg+M eXBqQApnNMqgw== Received: by mail-pj1-f49.google.com with SMTP id 98e67ed59e1d1-2855b3d9a9bso2557244a91.2 for ; Sun, 26 Nov 2023 23:42:23 -0800 (PST) X-Gm-Message-State: AOJu0YwK/E9QUkBLXrsxMME+1c/H6BlfJLnKx1S/+G68a7sSdWQCd17x y0VfcG31oqwGUhRQG5b/zdzsc3+XA1xmYOIcrvVIfQ== X-Google-Smtp-Source: AGHT+IE/9MLy2mP4Tya7d9XuqJFTMzuCQNibPnrO8JXb6SHZorbet3mA6rmkka/00WZDPzV9QBKFvE2tKxiEkrhrTfk= X-Received: by 2002:a17:90a:1a03:b0:280:2652:d4e with SMTP id 3-20020a17090a1a0300b0028026520d4emr9440658pjk.29.1701070942704; Sun, 26 Nov 2023 23:42:22 -0800 (PST) MIME-Version: 1.0 References: <20231121090624.1814733-1-liushixin2@huawei.com> <32fe518a-e962-14ae-badc-719390386db9@huawei.com> <87msv58068.fsf@yhuang6-desk2.ccr.corp.intel.com> <87h6l77wl5.fsf@yhuang6-desk2.ccr.corp.intel.com> In-Reply-To: <87h6l77wl5.fsf@yhuang6-desk2.ccr.corp.intel.com> From: Chris Li Date: Sun, 26 Nov 2023 23:42:11 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v10] mm: vmscan: try to reclaim swapcache pages if no swap space To: "Huang, Ying" Cc: Michal Hocko , Yosry Ahmed , Liu Shixin , Yu Zhao , Andrew Morton , Sachin Sant , Johannes Weiner , Kefeng Wang , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 76AA218000D X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 7oe96iwz8m7mzhwhtxm4ts8q9fiai6tj X-HE-Tag: 1701070948-358244 X-HE-Meta: U2FsdGVkX1/8e74y4WB+Htvm1jXoL3s8+Rr/Us5RMI5pwUZwvsBRltsX/gFai5TGj5yRgXptRIix01t4JJfp1uz+/BpB484D00l0CFo29f6c7uvcswjB5AXmLABwNuYStSMwtaWEnKnnCls6lZJ13Ow/X3ciQaHNyeAzIHLvb/rIj6fwZtGzE3atZZaWE1fw4Xj/6KpSmavWlodDZxO3f87q7lp1a7qe4+RKQnLArnGbayV07oZTRnA2aAD79ZTwWK+RIjIBjLnKW8trA6QWlb04+UoQwYf7AEn5aKO6zDDn2lWyZ3dYbtTpyx0mCeiS85K2Prj+CDjMHz2Puj00deu/lDyPj+XEuyKCGehq7yfMPHjSE9xB7WUkXXhEYmxKAJEhwFHHv1nt2hJOQcd7zWUpO5bBv4GFzh9QbaTrZdgqJRPtRd4rlj/JQtGGWrqZqAvH10/lbjFeu4cEG/o4Wa811hliA8NgLKvj8UnX5GB5Vzx39GQyLE8xNcItoNk6NEGI5NW0WGELhiV/v+Q+dADyPUV6SxwRUAOoUmBqhkTdxUEOzjcOqAEmo9M9HaSv0MzUL8z7tzUSxXWOhYZmcFEoJWvs92zLkGdECN7V5Mm/Tz0N5tildQjXNdO4bHzLvoXbt6nlRZOEuXbdKBOxLzzgNxKFiTmrRVKXZdDiH+gvsvI2R87BQwpsLp7zA2lOyaqKn6smslV7j0L5qux2k+thbEUGNOMhOz2tiOVSfH2eVWU3DBP2J5D2k4PgIHkkXwYB+hHD6q7ckFfi5xzKByfVb4MoRwkwazUdToJelotLGrQogVCRZrF/d0bHvrXs7knoClykthgoxQdm7GhTe2+xiWO+vYitXe1kxmTgAa+gXdHzEInWdYFndeLjMpn31vPuCG0F06+5ouG98vb85VuEAgJDZNNuk6DIIUss6ur6Ukzza9OdnhMETfsBwILPWYnQt7SXyX6eCxWQhO/ UIoOOLRr V7/SIBumCmmjyJHI9CBE3veIRikzclN52JJuIbw5dFHI6KLxiFCfwJmNQ9ATVrfAdBGoWO5kjdccGOwdx9gEt2WdU7XDL5/qvbFT74udxEqXAbkJsuoFHCfNjlK97ndC6Yiv7zEz/Ggka2bHU4TxiIa2mIej1pFVjDMLpyNAHv4b/G/AbwiHB77CwLsU7yR8Zj+0o9wLQ6uHMtyB00USDQeKw4+LqgPvjGy5ojUbPB01PSA7g+LhTsteN8xsqIBPeXPthGcVu6nF0DpM28tHv+7oYpWVP0aZI5NpU2EvzxC+w440= 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 Ying, On Sun, Nov 26, 2023 at 6:36=E2=80=AFPM Huang, Ying = wrote: > > Michal Hocko writes: > > > On Thu 23-11-23 14:15:59, Huang, Ying wrote: > >> Michal Hocko writes: > > [...] > >> > Yes swapcache pages are indeed more complicated but most of the time > >> > they just go away as well, no? > >> > >> When we swapin a page, we will put it in swapcache too. And the page > >> can be in that state for long time if there is more than 50% free spac= e > >> in the swap device. > > > > True, but why is that a problem? If you encounter such a swapped in pag= e > > on the file LRU then the page should be referened and as such should be > > activated, no? > > This just means that anonymous pages in file LRU aren't temporary or > short-term. So we need to consider that. For example, the original > method to balance between anonymous pages and file pages need to be > re-designed. The anonymous pages are considered hotter than file pages > in general. I agree with Ying that anonymous pages typically have different page access patterns than file pages, so we might want to treat them differently to reclaim them effectively. One random idea: How about we put the anonymous page in a swap cache in a different LRU than the rest of the anonymous pages. Then shrinking against those pages in the swap cache would be more effective.Instead of having [anon, file] LRU, now we have [anon not in swap cache, anon in swap cache, file] LRU Chris