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Shenoy" , "Swapnil Sapkal" , Shrikanth Hegde References: <20250313093746.6760-1-kprateek.nayak@amd.com> <9af4bb66-83c4-4257-bfc3-dbcb2185a7e6@oracle.com> Content-Language: en-US From: K Prateek Nayak In-Reply-To: <9af4bb66-83c4-4257-bfc3-dbcb2185a7e6@oracle.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CY4PEPF0000E9D1:EE_|BY5PR12MB4066:EE_ X-MS-Office365-Filtering-Correlation-Id: 3e649b39-375b-4ab5-eab8-08dd6a883432 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700013|1800799024|82310400026|376014|7416014|13003099007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?b1BYaTA4RkxONWIrdEtLM1QzOFZWT0w5WlRBbmp1MkFsMlJUWkg2N1k4ZTB2?= =?utf-8?B?Zk0rdmpuVmgxc0FpMXh6dTVPRFhhYzhjQXpPd2Q4Z3krWDNRTkFlQlZTR0lJ?= =?utf-8?B?VFR3NHhQOXRpY01DQkFaSW5DVXpWN3N5RGxqd1FJazhudVVNK1pzaFM4NGFr?= =?utf-8?B?ZW5lS2N6V2tJNkJrVnVXdTBkbUtZUUo2RERmYTExcm54RjdiaHZtbHdweEkr?= =?utf-8?B?d1ZJeFBJeG5IT1J4OEx2azlla2U4V09KUFNUUXV6VWd2MVZ0QVhhZVZFZXRI?= =?utf-8?B?b0dOZUNETnlQNVJLcFFwdklZam1zckxNYUdvTTVMVmEwQU1pZlFZbUtxREUz?= =?utf-8?B?clFabm03eEE0RDVac3RuN3l5TEY4dm1wQVpyK2tucWM5aVVPMUtYd0R1Y0ho?= =?utf-8?B?Qm4zVE1JVGtzbCtJVXV4cDlXYmxQbldReCtKVlIzRHFoNkVFQXZCd2RJR21T?= =?utf-8?B?QVpvcURtNG1DVkNmWC9LTmRmZUU0REV6UTZuS3M0TVR5dGJkRTV5d2dpUjhT?= =?utf-8?B?c2NNWjQvcExsQjZWelNUWTMzemJ2bHhBNE0xVjhKUE9Zak1PaWhUaFpkcEx0?= =?utf-8?B?dC8yNkY1WndUZTIvN2lBdTJPN3p2V01zNStlV25rNHlHUmV6NUZlMWwzbkI5?= =?utf-8?B?cTFSeDBXTnFyUzFRNTZXRmVmUHYvMmRpUlluQ0NkWTJNYno2NlJId0ZzVkIz?= =?utf-8?B?TUNFTXBTMHZjc3VhT0FaQ0hZLzFXTWg4MXg2azQ0TjZOcWsxTEZGcTBKTStx?= =?utf-8?B?NzNXVEdJbEJxOTJJbTBuYUx5UGxMYi9KK3YvWWZIWWwvaWxVN1BxQVdSK0F3?= =?utf-8?B?bjVMRzMyRkY3Mmh6ZzI0TXBmYTJOK3lJdndzUDBLMk1xS2h6WE9ibElpZW55?= =?utf-8?B?N005amNJeVhSQUNOU1lVazVTZ1NWL3R3TjlRUFI2SnZFTWRvRmxnRTRiK3Aw?= =?utf-8?B?aStxZXp0ZmsxdXA5SytOSisra0NWQUlsTXVwdzBRb3loa1pYdFV6Yk4wb1RU?= =?utf-8?B?ZFByaVJHMXNBeVM4M3RHaldtZjNaME5XeFlKYU1LZHgvaC8zM3NaLzJvbkw4?= =?utf-8?B?SVYrSGZVNDZlL2lDY3hKTmZqOGdab1hGOEx5cjVqYVlLcFRlN3JzTElSUW5N?= =?utf-8?B?OW9DQlppSzF2S3U5MXAwOVFIVUVJZVM5RHRBZCtTSnRJVUt1S2UrYVdaS2xq?= =?utf-8?B?WWxUYUU4SVI1U05QY3FZSDRkZGNCaTQyeTVjRSttS1pwOFU2MzVQUXBpYmE4?= =?utf-8?B?Y2xJWFQxaTVZWXJkcDZPRUtMY3h1aVhOcUtIQXV4OWNJQS84L0kvRGtlYm5y?= =?utf-8?B?WjJIQ1BEaWJvMkNoMlh3UER0bHczYUZKajVGNmVPVlV3QnRIWFZTQ1crRTR2?= =?utf-8?B?RXEwUUV2Wk5pNXFQTEJuNmx0L3JGTnJYaUtwdFVMVFc2VXluYkVGZlQySFVw?= =?utf-8?B?eGJtQjdNSEhuY1llRDVnL0g1bnZqbjhkaUxZeXgrbEhvNWs1RUFUYTVnV2VS?= =?utf-8?B?b1FsN3VnUkhtblR0NWR1akQvSklpV1RGR1JjUlhLMEVqQUhKUHBWbXl5QW14?= =?utf-8?B?Uk1mNVVvYlEvQTQvOGQ1SktaYyt3dFo4NkpCQ0gzTXhBS2t0Q3E0cjN2L1Ax?= =?utf-8?B?WitrNyt1T2FUUER2SWNGL0l0V1laNmFyVDNjaFJWSUhZQkZJRmw1QXV5Wmlj?= =?utf-8?B?ZEVxUVpvcVZvUStZNzR6cmhjUkNtRnUzR3N1bXpicVBXTW0wbmhBYldDOEQ0?= =?utf-8?B?ZEtSVVFMaWZSZTdhczU2U3hsUm0wTUFTOElOWUpxUjYrbkZPVmJSQTM0Mnp0?= =?utf-8?B?enlKTkdCbjBXS2xud2E3M2FtRXNjMk4yMGhXalk4VEFuZ0pTZHMzVktGR2FG?= =?utf-8?B?MTUrZHUrTmRkV1B5cFlJUFJIYkRWNkYza3NHc1pTWG9xT290bVZXN2RxZmN1?= =?utf-8?B?VGVFU1c5czJudlRLbTdlbndlWXE1bDlFM0lLOW1YSStCeUhPUG5GdHZGWS9a?= =?utf-8?Q?aZmTYfhvhQFslQk6ufGq/XwT+cMHM8=3D?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:SATLEXMB04.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(36860700013)(1800799024)(82310400026)(376014)(7416014)(13003099007);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Mar 2025 03:58:57.8608 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 3e649b39-375b-4ab5-eab8-08dd6a883432 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CY4PEPF0000E9D1.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB4066 Hello Libo, Thank you for taking a look at the series and sorry for the late response. On 3/21/2025 3:34 PM, Libo Chen wrote: > > > On 3/13/25 02:37, K Prateek Nayak wrote: > >> Benchmark results >> ================= >> > > Hi Prateek, > > Definitely like the idea, esp. if we can pull this off on newidle lb > which tends to be more problematic on systems with a large number > of cores. But the data below on periodic lb isn't I guess as good as > I expect. So I am wondering if the cost of update_[sd|sg]_lb_stats() > actually went down as the result of the caching? I have some numbers for versioning idea that I got working just before OSPM in [1] The benchmark results don't move much but the total time for newidle balance reduces by ~5% overall. There is a ~30% overhead of aggregating and propagating the stats upwards at SMT domain that offsets some of the benefits of propagation at higher domains but I'm working to see if this can be reduced and only done if required. Some ideas were discussed at OSPM to reduce the overheads further and shared the burden of busy load balancing across all CPUs in the domain and I'll tackle that next. If you have any benchmark where this shows up prominently, please do let me know and I can try adding it to the bunch. [1] https://lore.kernel.org/lkml/20250316102916.10614-1-kprateek.nayak@amd.com/ -- Thanks and Regards, Prateek > > Thanks, > Libo