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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?hmnSRmquMepqNvcVNNoGyZqwJ0N0Zbn0KcOEmEX+AN2NUSLOq55gsLfjqAjc?= =?us-ascii?Q?pe2LDqHZfWng+GMR0YXVRuiiFwf2X5Th+0ibC2jINy+WwQRqCsm510Ysxhko?= =?us-ascii?Q?8aSCnUjMe/aul40fkn/EhnxuXdWTb9DvmQKUhX8jA6Pc0cLtyvTvTBHks4Rq?= =?us-ascii?Q?Hbw76Dhq5cHwzPBJ4qAlDsXqy7uiHgyErtpaoW4lAcsbJoJ6g+kXtCBrAUQ0?= =?us-ascii?Q?Balz2ghdQfoRCbUiB+UOTYo44BsZ2PomEtWYlt8KR+Ukkg0nPoCl+TCqdAtN?= =?us-ascii?Q?ycp2u9T9eVbxrDrbQ51iWuJJ82ULhy8tv/pB0IDP/0dekySXewoiGmD8ANBC?= =?us-ascii?Q?CozDUzFMAlfP7gef/5licGxohsxf0WjFSt3UPywgCq4WcJkdi38A6xExZwIp?= =?us-ascii?Q?RRhBLxBSIr46bHi3gwBLsru5VrPRGq8L4yQyiXmq0KGmdxCtwsZMwI7VoM2T?= =?us-ascii?Q?VlkbrkZKNuA/inRO0z6YpZqhY7FHF1fMtBkwyq5Ftxr95ApBmnc5JTH3Re6z?= =?us-ascii?Q?R04A1lQ9zdWw2ofG4qedlRl6S4MKorVmx0SmiJ9m6VoI1T5t6RksymsK7wOQ?= =?us-ascii?Q?JX+2dOeWW6LOA6WldBzw3kP46+uu872IbBBczxh5NGR1UQw+XBeCoAN2Ei0N?= =?us-ascii?Q?WxRS97Nf020i/UIc02ltQoAtLtCyjH7ZZJYLlL68HrvXkYkcrUA/8oRwW3ao?= =?us-ascii?Q?/vM4KK+pL19vGkVxC3ZoPuQcI6BqUmWdFyQ3R71ueQrGW2KlaQB51g3T5Zt3?= =?us-ascii?Q?EYe9GN9JSPfGUCOWp0pGbydciJihp5uUGc89nrt4WgI4JmdiijgUrwyeR96L?= =?us-ascii?Q?mY+Jd0gc2YFBRc1nkFxxEP/38QLB9CfherxRv5ggt43tJXy285Vxtm4gZ8Jn?= =?us-ascii?Q?T9vU7ljjisIbSoLRukEr4z0iVIuFTYwskzHikg0hHu4VH9vtIs5eFwFxVM7r?= =?us-ascii?Q?JR9N+H+gvE0ZY/e3pOS2biIvMsvE18dVD02Vj3mZszRY8GXG5732pIy/PoMP?= =?us-ascii?Q?RXrYY67MD06fFsJqwUIBkPxWxsjOpPgXTW6LGpBH1gYCKLtAxmFl7kIMEod6?= =?us-ascii?Q?UmQilYAdcIujivAIr/PTkv2plm6KPw2Bk9XHK+bOfwm74X2mEbZbLM3gGC8p?= =?us-ascii?Q?6vt0AQArT6lLvfj+Oi2UaCyJp+KQukWh8eA8WLgB21zfe8/yi7MAyzrDIha1?= =?us-ascii?Q?8KRWVZWwHf450t8alZpyNjwLJAX8wMm/HAcwKn89mDQXkc9JaXZ97/DM30+3?= =?us-ascii?Q?J1TIrQ6hKCql51KJzGOSU7SyTJN2qXscFO+d7jLWubdVs+gk7pemrMUuWL3v?= =?us-ascii?Q?qGhcjCWtzeJ9vjU5xz/ZepPuEXjeQTyZdMC2jpzcfUMBY7303nVmXahPA6SR?= =?us-ascii?Q?oshabmGQbJHT5xQmY/Fo3Wd5/pUpelAQPF3lhrIh5N3HzjQZ4GdA4AbZEhTt?= =?us-ascii?Q?LVDYyqaijiTsbCdt0fYRv4ATaD5yN/DcwfIPMLaK0b/eyHQGx4SnNVC0X2eB?= =?us-ascii?Q?NU6B0IyqhR3yjZlIPwJj8/kfLvkdPc8uXwEdyZkiSZARI49INTdsteHenCyF?= =?us-ascii?Q?AZmu3E07kbYyqdWt71lbb7N9iwcqReGaYBJJNG2T?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fa67f585-6349-4ca0-dea8-08dd207278d4 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Dec 2024 21:16:58.3397 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Qrz8qy1VnTn1m0Q0Us+QRic+Fw/KE3lFYnGP4WCkFhjv8r4q/vvViPbaY6W57p97TQPT9kLLRspt0ooxCnag5A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB9005 On Thu, Dec 19, 2024 at 08:52:30PM +0100, Peter Zijlstra wrote: > On Thu, Dec 19, 2024 at 10:26:59AM -0800, Yury Norov wrote: > > > Given that there usually aren't that many nodes, the current implementation > > > is probably fine too, so please feel free to ignore this suggestion for now > > > too. > > > > I agree. The number of nodes on typical system is 1 or 2. Even if > > it's 8, the Andrea's bubble sort will be still acceptable. So, I'm > > OK with O(N^2) if you guys OK with it. I only would like to have > > this choice explained in commit message. > > There are systems with 100s or 1000s of nodes out there. As long as > hitting this code path is optional I suppose that's not a problem, but > if not, they're going to be rather upset. Right, this code is optional, it's only hit when SCX_OPS_KEEP_BUILTIN_IDLE is enabled (off by default) in an scx scheduler and the scheduler is asking for any idle CPU in the system without speficying a target node. So, it shouldn't be a big concern for now, and we can probably add optimizations for special cases later. I'll add a comment to explain this as well. Thanks, -Andrea