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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?vx9p0PUT6s/13IoruqbO5e9oo/oBSaDLQfNFucYZunSykaWroxlmK1sjy8RL?= =?us-ascii?Q?Lc6hwgwfiXu/03XOHNbluSmr+MGALmqna3KVHJ36h0N86wD+9UVuUjVqHa4G?= =?us-ascii?Q?7z74XBSy6x06I+vdxr2RETwsY+oAaV7z2uBxnpPLHDNhPj+FJJah2iTB1vko?= =?us-ascii?Q?0RWST8LE0zcoLWN32k8zLs6ORMR+g3uecfrjLMMLSiLoZmtgoioFqJcQYUk6?= =?us-ascii?Q?S8J9HbZM54mQdLBgiVnb+MYE/NmdW2EVHrIs6eclTZqz8uJNu/vOQyusTjQD?= =?us-ascii?Q?8mbNsL3LPLjKR1E94Sz5j7U7pxx1dQU1sShBKBco76QA7QnJMT46An18xQMM?= =?us-ascii?Q?lM8OfDi5XfIynVFQqdoe7UT+6ZvPiG7EHwRmF5xl1w3uYsURtZP6hmIo7kOi?= =?us-ascii?Q?p/HNbI55vRa36yJzPf4kk9zKtUXPQV+POCaoxCD91I79sP/Z66Notn2+R1Ud?= =?us-ascii?Q?I90dy5CZnmcmJLBVkqlDKUjpkzqG42d6zFd8EVmGK//u5q41O1wn/Ek8+DEy?= =?us-ascii?Q?5/p6IUtppvX+BBlgBcwmMZ9+odCYdpt7Hi80+SHbDf19+DaetPUsG6wWF+1k?= =?us-ascii?Q?HD+ntNPKQQ7hP61244p8jl7Gpx35/tevigDUQnm0hMBixzugvanfbBb2Eulg?= =?us-ascii?Q?SWOxFeC6+qiswoZIP1FsqEg8+qr4L/5l6X4WKZNsB1kzmtFK2bCZpzANKX+/?= =?us-ascii?Q?WpBB3ezLTj1fJYUbUG252SPJKZaKBYAu/GUpy/W9vS//zLOaG/lWUpeGEpdm?= =?us-ascii?Q?Zd0Tlf46oXhAmb5+Tvzg/2knyrI8xJ2YA4nAxTe0++p4Y3CbT5PQQndQwEHv?= =?us-ascii?Q?y636xFRAxJB/q+tPCJhxvBrksZkYC5n7sJZSDfxp3X3N1eiTcJUSycMoBOzx?= =?us-ascii?Q?/k+bCDbehNBTrKe/vUd3NzpCF/IwKZQeHIOdGgjVYhW0ClQz7XqXAI5t9BP5?= =?us-ascii?Q?uO5mRYHVg7HvmeOCzlGflbka1TIBx3P8HmkDLLjOaejFgdxV9sCgLF+cYo9b?= =?us-ascii?Q?oC7wMGKeddACf3A5EDbCIOzZZpmsHz56kQBzNgWbiymg1k9IbZSzYq5B7miL?= =?us-ascii?Q?08jcGhPQbvMMzVdZJRDpdIjLuotGggs1IaBh6gu3KyK1+r+IawbrB3eqFSBl?= =?us-ascii?Q?idvO/U6525cgGKdFeP2tj3m+bYF9xU20LWRqOFtldeorgGWcRuGS4g+BvCyv?= =?us-ascii?Q?0XkNBBCwQCKbE0dvVn+u8F4kDRk5N0brmP9+CLKXS0H96Tdnb1BVf1t7FeGu?= =?us-ascii?Q?mIk9RNOwLMyhJArgvB+S17jfvjjQ2wxluxNqeThrwuPPl1ZkIv6uYui8QveQ?= =?us-ascii?Q?PxugtmGymeCzuuGMWjkIEPa6xhgNzunsMbTb7ZjzGMX2Pur1dk8jAh/mQCQP?= =?us-ascii?Q?zmd7lKii/5mWrN74OJ27r+H7urS+AsUI8NV/QWPeYPH+j/pYQD/UW/nRfBtc?= =?us-ascii?Q?hHBtQtWTDg9ji3o7ujoVFo1SLzgdYPOheIdu2oCLj5ILbIJtFKLCgsrrEBtX?= =?us-ascii?Q?G35eJc3m7eOZfFKJdkmdzhp0nnuCQoFRkLR34NGrKOkQO77HwZcmUVyCVMzA?= =?us-ascii?Q?aCgnAbWqpqsmvk4Hme1aTnwkTMZCZQVdPCAOFzwN?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4c3b537d-300f-496f-1e9b-08dd47cb2628 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Feb 2025 23:00:00.1767 (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: Gm8v/qW04rMJWBQUohAG4xpbcU1FAP5Vt2woh/OfP8MKxdLEupiinJMt2DK0Yj6T477aYDxAIyfgfNhDoujPIw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB7827 On Fri, Feb 07, 2025 at 12:44:07PM -1000, Tejun Heo wrote: ... > > I'm also a bit conflicted if the default should be on or off, we're > > changing the previous behavior, but OTOH this is going to prevent some > > potential breakage (due to the nr_cpus_allowed mismatch) and server > > workload is going to benefit from this, so it seems that there are more > > pros than cons at dispatching migration_disabled tasks directly by default. > > Hmm.. I didn't see a lot of migrate_disable() while testing with stress-ng > and migrate_disable() isn't used that much in the kernel to begin with. Do > you happen to know where migrate_disable() was coming from when you saw them > with bpfland? I also don't see a lot of migrate_disable() invocations, but if I do the usual benchmark, measuring the fps while building the kernel, with the migration_disabled tasks dispatched directly I see a significant performance drop in the fps and the kernel build is faster, so it seems something related to the IO? I'll investigate a bit... -Andrea