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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shakeel Butt , , , Subject: Re: [RFC PATCH] mm: use precise current RSS for high-water accounting Date: Thu, 23 Jul 2026 10:07:08 -0700 Message-ID: <20260723170710.1971749-1-nirmoyd@nvidia.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <21d24fc4-141d-4957-8b96-6d5887ef4027@efficios.com> References: <20260723134158.1473841-1-nirmoyd@nvidia.com> <20260723162133.877125-1-nirmoyd@nvidia.com> <21d24fc4-141d-4957-8b96-6d5887ef4027@efficios.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain X-ClientProxiedBy: rnnvmail201.nvidia.com (10.129.68.8) To rnnvmail201.nvidia.com (10.129.68.8) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA2PEPF000015C8:EE_|CH3PR12MB8660:EE_ X-MS-Office365-Filtering-Correlation-Id: 56084cd6-7443-4dc1-95df-08dee8dcea76 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|82310400026|23010399003|1800799024|36860700016|56012099006|11063799006|4143699003|10067099003|22082099003|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230040)(7416014)(376014)(82310400026)(23010399003)(1800799024)(36860700016)(56012099006)(11063799006)(4143699003)(10067099003)(22082099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: foPolEPhmvRd8a5kJOAgM1uqXoLaOFLxW1OXuP1y9oqXR6Weq6VsYzANDYO4uZlyf9WpR9j8XKgxfE2X78eKPde6mGGwg64ypo8HCkNdnncmTT9k2Js9qw6K36uP/5GyB1s3coZhQExlQ1Tt6zBu8yrG+a2oG3fMmVXd3s7NplKaM9k1BogbtgMWz8r6nt1cnF2hwADS8y4KNvLnKV1WycrUXK/60nkb7MNpWH9GLv9I3TJuBCZ7A76XtNtQc5Ji+fQkI70wpnoJifO2ViuVkbGnZZEpWLJIK8FihwMndWiXC8UyeoFELzzIS+RXRePS3eBUvOufRENv54AQiyxIAjT7nq5uIKjn193v14ejJtf6kzhZ0uLzKSq4c1EgOPeDExos09bU7Oz/FsojGRPkpondfzfnvx8Ucpumli5r2Cfz8VpIdVl0pwQVoAncawzh X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jul 2026 17:07:45.5751 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 56084cd6-7443-4dc1-95df-08dee8dcea76 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: SA2PEPF000015C8.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8660 Hi Mathieu,=0D =0D On 2026-07-23 12:31, Mathieu Desnoyers wrote:=0D > What is this test validating ? Does it actually matter for a real-life=0D > use-case, or is it just the test being too strict ?=0D =0D It tests getrusage(RUSAGE_CHILDREN).ru_maxrss:=0D =0D https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/sysc= alls/getrusage/getrusage03.c=0D =0D I am not sure about a real-world use-case; I do not have one.=0D =0D > What is the overhead impact of your change from approximated counter=0D > read to a precise sum on this /proc ABI ?=0D =0D I have not benchmarked the overhead yet. I will get back on this. =0D =0D Thanks,=0D Nirmoy=0D