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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2853D10398B2 for ; Fri, 27 Feb 2026 21:27:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6799F6B00D1; Fri, 27 Feb 2026 16:27:22 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 626E46B00D2; Fri, 27 Feb 2026 16:27:22 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 55DAA6B00D4; Fri, 27 Feb 2026 16:27:22 -0500 (EST) 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 498596B00D1 for ; Fri, 27 Feb 2026 16:27:22 -0500 (EST) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 010941A06B9 for ; Fri, 27 Feb 2026 21:27:21 +0000 (UTC) X-FDA: 84491522724.29.FE6CBEC Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf26.hostedemail.com (Postfix) with ESMTP id 2ACEC140009 for ; Fri, 27 Feb 2026 21:27:19 +0000 (UTC) Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=h13cm9u2; spf=pass (imf26.hostedemail.com: domain of akpm@linux-foundation.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1772227640; 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=8nr8QjvS3mLZizbI7j3rfqhpd6Mz9hXA6KgKYNW+FqM=; b=CZRR+6lch8OeFI2Zq/lb/58vlA3ynMDJ1O8CgrXGO4gSjyxTkaVyW5ddV/hopSbxeMIe1V kw1n5mbkq3tFjMIQ8UXOLbUfQ9LHcmMY//tbUwKRpPbRm3Kqk+RbHfRgACVskIU+xtaDXx CDLX9lFJv6cvU3lonP5O1ubV7hHDo+M= ARC-Authentication-Results: i=1; imf26.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=h13cm9u2; spf=pass (imf26.hostedemail.com: domain of akpm@linux-foundation.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1772227640; a=rsa-sha256; cv=none; b=BSO9KnwoVBY7cGg8OfRed1b7jbNWOzGYruE1Y2CNSGPdD0cXa9CVnlr0YjUzEgGhL6GwcB QrIhXML70MMfaKununifbsV/RfiXno0OxKzGtE+5jMkx58kGa4tm2+96g4qKwWdGUKDYuh G0VXnQn1eHrMwPTmKfKMXHxh61sLFOc= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 1BDDF43E97; Fri, 27 Feb 2026 21:27:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4FAAC116C6; Fri, 27 Feb 2026 21:27:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1772227638; bh=WDjPZKs4MqgqqUaiQyuXBaE6TTaaT0C+D7IxDQoFPjE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=h13cm9u2Haz3r+0D/dv7uzmEiEhrbak0bfbOKms+/VF9CK1wFmohzV7Oc2f4ltVpX VkDYOqGRahVOKkttbyX/W2TGuCe698IMvn/RjFUtJJFvyy9pwrEKCg3RkvJ4XXZUy/ 8iSqa17sXW/GLsZzyuVqRAoCPzeW0Obx7rikUoW0= Date: Fri, 27 Feb 2026 13:27:17 -0800 From: Andrew Morton To: Mathieu Desnoyers Cc: linux-kernel@vger.kernel.org, "Paul E. McKenney" , Steven Rostedt , Masami Hiramatsu , Dennis Zhou , Tejun Heo , Christoph Lameter , Martin Liu , David Rientjes , christian.koenig@amd.com, Shakeel Butt , SeongJae Park , Michal Hocko , Johannes Weiner , Sweet Tea Dorminy , Lorenzo Stoakes , "Liam R . Howlett" , Mike Rapoport , Suren Baghdasaryan , Vlastimil Babka , Christian Brauner , Wei Yang , David Hildenbrand , Miaohe Lin , Al Viro , linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, Yu Zhao , Roman Gushchin , Mateusz Guzik , Matthew Wilcox , Baolin Wang , Aboorva Devarajan Subject: Re: [PATCH v18 0/3] Improve proc RSS accuracy Message-Id: <20260227132717.c811f04b63a332f88e354e08@linux-foundation.org> In-Reply-To: <20260227153730.1556542-1-mathieu.desnoyers@efficios.com> References: <20260227153730.1556542-1-mathieu.desnoyers@efficios.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 2ACEC140009 X-Stat-Signature: hsh7itnf9rctceor4rzp51ntfajcox4p X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1772227639-704763 X-HE-Meta: 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 18bf3Sxm V6ja6AbKVuYbKaGrGYk26Bm6g8HK9s2XRVLxGfUNgsNSQ5piCJ9+herQMpZIs6B0pFTXNm9m616D7Q2QP9AyDRQW9AZSh61z7FOwGoNksGSiAilEzP4wwcKsgeBjKF5KmLvfi+Lt63V5/c8+0qogiDbHLydI2x0u2PMkKyRXMzT2l0El+BpuNpHNVxU99H3gbVkU+23eyirv6F97H/vudrWeUB7gABylWfTI8iCmUvkYOPtPAoS0V3LEs2vXwN/cbdPz7fE4ohK54GqqPpUs9Xba94nGkD0o0n3Lmz5MrsvXFHb2b6hy8+V/M/PAHWei3jKmwydOI85P0RDaxll+Sl84wUgTOS/BAMl1EzEMZAzB8uzwFiOp6pV3HlOA3uswm44NI Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 27 Feb 2026 10:37:27 -0500 Mathieu Desnoyers wrote: > This series introduces the hierarchical tree counter (hpcc) to increase > accuracy of approximated RSS counters exposed through proc interfaces. > > With a test program hopping across CPUs doing frequent mmap/munmap > operations, the upstream implementation approximation reaches a 1GB > delta from the precise value after a few minutes, compared to a 80MB > delta with the hierarchical counter. The hierarchical counter provides a > guaranteed maximum approximation inaccuracy of 192MB on that hardware > topology. > > This series is based on tag v7.0-rc1. > > The main changes since v17: > - Fix patch series bissectability. > - Export GPL symbols for kunit tests. > - Improve kunit tests coverage. > - Fix kunit tests wait queue head reinit bug. > - Fix an out-of-bound on bootup on configurations where nr_cpu_ids is > close to NR_CPUS. Updated, thanks. > Andrew, this series targets 7.1. Some review would be useful. Can you think of someone we could ask to undertake this?