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 D4448C433FE for ; Tue, 18 Oct 2022 22:54:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 73E256B0071; Tue, 18 Oct 2022 18:54:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6EDBA6B0072; Tue, 18 Oct 2022 18:54:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 58E9C6B0073; Tue, 18 Oct 2022 18:54:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 46A156B0071 for ; Tue, 18 Oct 2022 18:54:10 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 1B3E51405FF for ; Tue, 18 Oct 2022 22:54:10 +0000 (UTC) X-FDA: 80035575060.06.134E1E8 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf23.hostedemail.com (Postfix) with ESMTP id B4D7B140003 for ; Tue, 18 Oct 2022 22:54:09 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CFEDC616FF; Tue, 18 Oct 2022 22:54:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E655FC433D7; Tue, 18 Oct 2022 22:54:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1666133648; bh=62ein6zk//FYRqXxpk4NDw+VTD3FYrLTczKhbyNmhTA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=kuIsBb/jJu+Rb0wN62bc6xOuq8iX6x/+dLOeQscUmPiKFEfN6wELKwD3WtRjcpVbD o1GKVuOj7os7ZJLQpjdXhB/GIczm6coNTWBqodL8slCZlHzaMW9CXDfq2LwsXMfCIW uXnMVPTPd/W+6aejFjGP85YFK6G/gY1hSucfx4LM= Date: Tue, 18 Oct 2022 15:54:07 -0700 From: Andrew Morton To: xu xin Cc: david@redhat.com, imbrenda@linux.ibm.com, jiang.xuexin@zte.com.cn, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ran.xiaokai@zte.com.cn, xu.xin16@zte.com.cn, yang.yang29@zte.com.cn Subject: Re: [PATCH v3 0/5] ksm: support tracking KSM-placed zero-pages Message-Id: <20221018155407.41c993924ec09a64ae966d50@linux-foundation.org> In-Reply-To: <20221018090022.373574-1-xu.xin16@zte.com.cn> References: <20221017165541.6e2d3cebdc1ba13861ea4b2b@linux-foundation.org> <20221018090022.373574-1-xu.xin16@zte.com.cn> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="kuIsBb/j"; dmarc=none; spf=pass (imf23.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666133649; a=rsa-sha256; cv=none; b=GKXeAW2q4NwPxdVsE78QKLQh7ykYnZuczJrI6Lj7a8jJZBI29C557UYJaqTe0kqHU8N1Xg ThKN6K/immiL9wW+Jsvdr20YoKlz9ZMpilwSoP+F5dSDrQHe+HFGtM9u7cLimZmtxCuVFK 0ZJz6+IoA7owEstu/X5yTkEdoq0M3N8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666133649; 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=O4+WHcui1muOaNmQ9Od4il6vBqX7LULZhq/r+qaUImo=; b=fotO2eZ3v56NVOpMUjmCZa3cP75FabOSLmzhySf5q5PenpUs+0kPdQckK96MUAp5XbcG0z b5F+Me/pbYzGw4oQ+evosEWJrP3gOFspdX0qda1yy6bLAW00/OrFlu3hHsUjv+a6p3sQK1 g2r6t80YtynOejqEKIUUIgTPU0/dkxw= Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="kuIsBb/j"; dmarc=none; spf=pass (imf23.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspam-User: X-Rspamd-Server: rspam06 X-Stat-Signature: zag36y7d1d9pnqwnse9c3p6qqcd6t8d7 X-Rspamd-Queue-Id: B4D7B140003 X-HE-Tag: 1666133649-387404 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: On Tue, 18 Oct 2022 09:00:22 +0000 xu xin wrote: > >A full description of the real-world end-user operational benefits of > >these changes would help, please. > > > > The core idea of this patch set is to enable users to perceive the number of any > pages merged by KSM, regardless of whether use_zero_page switch has been turned > on, so that users can know how much free memory increase is really due to their > madvise(MERGEABLE) actions. OK, thanks. > The motivation for me to do this is that when I do > an application optimization of KSM on embedded Linux for 5G platform, I find > that ksm_merging_pages of some process becomes very small(but used to be large), > which led me to think that there was any problem with the application KSM-madvise > strategy, but in fact, it was only because use_zero_pages is on. Please expand on the above motivation and experience, and include it in the [0/n] changelog. But let's leave it a few days to see if there's additional reviewer input.