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Wed, 25 Feb 2026 15:40:05 +0000 Message-ID: Date: Wed, 25 Feb 2026 23:39:54 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] sched/topology: Check average distances to remote packages To: Peter Zijlstra , Kyle Meyer CC: , , , , , , , , , , , , , , References: <20260223170314.GU1395266@noisy.programming.kicks-ass.net> <20260225123052.GN3016024@noisy.programming.kicks-ass.net> Content-Language: en-US From: "Chen, Yu C" In-Reply-To: <20260225123052.GN3016024@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SG2PR06CA0197.apcprd06.prod.outlook.com (2603:1096:4:1::29) To DM4PR11MB6020.namprd11.prod.outlook.com (2603:10b6:8:61::19) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM4PR11MB6020:EE_|DS4PPF0442004E1:EE_ X-MS-Office365-Filtering-Correlation-Id: 062cb74b-c103-403b-ba71-08de7484257e X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|376014|366016; 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> + long d = 0; > + int x, y; > + > + if (!u) > + u = slit_cluster_size(); > + > + /* > + * Is this a unit cluster on the trace? > + */ > + if ((i / u) == (j / u)) > + return node_distance(i, j); the u is 3 in above example, because slit_cluster_size() found that node0, node1 and node2 are in the same biggest symmetric cluster. Not sure if I understand it correctly, here we will treat node4 and node5 as the same cluster, but without checking whether node_distance(4, 5) and node_distance(5,4) are the same. If node_dist(4,5)!=node_dist(5,4), will we keep it as it is? thanks, Chenyu