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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 00B0EC433F5 for ; Mon, 10 Jan 2022 14:51:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=2KtMpkHrgJCsvi0oe9xqo6Ha7BupSTouQzJdQ4dplSg=; b=rn7PCJGVExk1Xs nnIAtBJieJ99bJTA12oCAzfbmUcPnlPnzpi/FkGc1urUgVIlMX+9y2FCektuFCVaSgTbs8n41VZME AxjyY1XlfMiXC40zkWJxGm6Ig+K5k3ZhgdKpMkAoi/bbEYg782jVKQtm8fhqzt/33oK1ttboPV7cw juCgRghpQfi//Ts3VOZ9R3/xj88a18eWUciN0JDGWeJMJdHSGxDtcpyXjbE7XQNDQLeVx6jZOEJF0 cehdmmW8kXI/wJh0iULGKpuZkyoP0lEjsrx2aJM+902YQTfeY7yPJXbpDX+9U9wUMNep5B0fOkaFJ 7nff+2u4D5o9fKhrtMdg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n6vzl-00BuOw-8p; Mon, 10 Jan 2022 14:50:01 +0000 Received: from shark1.inbox.lv ([194.152.32.81]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n6vzg-00BuK4-SS for linux-arm-kernel@lists.infradead.org; Mon, 10 Jan 2022 14:49:58 +0000 Received: from shark1.inbox.lv (localhost [127.0.0.1]) by shark1-out.inbox.lv (Postfix) with ESMTP id 048B61118140; Mon, 10 Jan 2022 16:49:48 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=inbox.lv; s=30062014; t=1641826188; bh=v8M5awXlRgm8CQPFWrxz5Yn/2aXPYkjUaIMnTlnA2j4=; h=Date:From:To:Subject:Message-ID:In-Reply-To:References: Content-Type:X-ESPOL:from:date; b=ETkKyFBSqlmwxhHpOAPlyeai+0JG5EsOAxPGfHaxqA+mKrNVrafW5wHuqE9QQOdMj fkYp9FiHF5ouPE742u0Z4OYws+vdRodvMKwZg4yPdnwSk2m8KG7fxrtK2j6yOU0Fju hYNdJxDDysBQmZCy8v1k5aZExcslKHO6gl19u3Sw= Received: from localhost (localhost [127.0.0.1]) by shark1-in.inbox.lv (Postfix) with ESMTP id EDA2011180B4; Mon, 10 Jan 2022 16:49:47 +0200 (EET) Received: from shark1.inbox.lv ([127.0.0.1]) by localhost (shark1.inbox.lv [127.0.0.1]) (spamfilter, port 35) with ESMTP id 49NQ99mX1Zp1; Mon, 10 Jan 2022 16:49:47 +0200 (EET) Received: from mail.inbox.lv (pop1 [127.0.0.1]) by shark1-in.inbox.lv (Postfix) with ESMTP id 9C3971118085; Mon, 10 Jan 2022 16:49:47 +0200 (EET) Date: Mon, 10 Jan 2022 23:49:32 +0900 From: Alexey Avramov To: Yu Zhao Cc: Andrew Morton , Linus Torvalds , Andi Kleen , Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, page-reclaim@google.com, x86@kernel.org, hakavlad@gmail.com Subject: Re: [PATCH v6 0/9] Multigenerational LRU Framework Message-ID: <20220110234932.6eb6c356@mail.inbox.lv> In-Reply-To: <20220104202227.2903605-1-yuzhao@google.com> References: <20220104202227.2903605-1-yuzhao@google.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-Virus-Scanned: OK X-ESPOL: AJqEQH8B6gpL2qWiUuRh4Or6x9a2SFs9vyXmrMk96HRYtbrGu9h2dXPmZYmvRkKl X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220110_064957_112209_92822812 X-CRM114-Status: UNSURE ( 8.46 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Note that with vm.swappiness=0, the vm.watermark_scale_factor value does not affect the swap possibility: MGLRU ignores sc->file_is_tiny. With the classic 2-gen LRU swapping goes well at swappiness=0 and high vm.watermark_scale_factor, which is expected according to the documentation: "At 0, the kernel will not initiate swap until the amount of free and file-backed pages is less than the high watermark in a zone." [1] With vm.swappiness=0, no swap occurs with any vm.watermark_scale_factor value with MGLRU. I used to see in practice (with MGLRU v3) the impossibility of swapping when vm.swappiness=0 and vm.watermark_scale_factor=1000. At a minimum, this will require updating the documentation for vm.swappiness. BTW, why MGLRU doesn't use something like sc->file_is_tiny? [1] https://github.com/torvalds/linux/blob/v5.16/Documentation/admin-guide/sysctl/vm.rst#swappiness _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel