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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?M13sESqc3XfIgScs+d/S32WNumNL3IOJC7Ubcer6jLcb/hCx2/QmLA8Y2e+U?= =?us-ascii?Q?PaW5Yb5LPPd6tKEvHUs0Db/K5Rn1/vL95olyh0PiAXEjcY8CJg2NDHn/GgCt?= =?us-ascii?Q?JCwYnc/8wmPl6VXK6O7RV+nJhN6pOv6iqIGhvhaGSG8J2uXKAW57BN47T0Or?= =?us-ascii?Q?RW7k4ogL6/4ujFjc4yY7od6SqJKXpAqARW+2oP76GSPinItTgJNcnpJ6Vvgp?= =?us-ascii?Q?r+Bht8oJ/+acvDOuszQdxns9eGULNXfDOjaS6G6j+yBIj96/7Ow/XnmxQ+Jf?= =?us-ascii?Q?Ej+OIY6dBg6Sm2uN8IL8qQVkwnfn5R2GHuEd1tBSA9XSBy0GgtwdnP0OA3+O?= =?us-ascii?Q?NOQzdzewfv9vvtCOSF5yJHnYFYArTHjJPLtxMkpUJaX+PbL5j09yRDX9IhwZ?= =?us-ascii?Q?L7IdJrhLBPL9syhdtY4DVozNtKuA0rkWMpxEdYQ1PkmirosFbO4YD6186Bdk?= =?us-ascii?Q?kXsqiKzy8rGgyePL7dvvo1bacCCVucZ6PbD+GxMa5+4NtOjAhN75Punyi4tv?= =?us-ascii?Q?TiZAxKobonIqtbkHX+blg0fP7zh3Qu0cG5sjqDhIV8LWjhsNcSHR/GNGqyUB?= =?us-ascii?Q?tEKLBZ2VNaCkp0/YF9thVs5sUMxRTonF1CY84CNukT8cyD6XOTkB9GF2hcQl?= =?us-ascii?Q?kDeLzGVHCUXyXi7ZxtxxwTkOhX3mHWBI26YwRcepyjbvo/Ve7qHAdAXVR0cZ?= =?us-ascii?Q?VQulBy/nhEODW5t4d8RKSYL2dQhvGPFQX99TOf6JrITLeuZYfQzSDUGeI8F9?= =?us-ascii?Q?r7sb39XaKHWPB4cWADM96VFa0BjENGmJWpCxgiNLDrBGmzZJcGzW2Fvvel59?= =?us-ascii?Q?EsMbDkBmt3pdiyrEuG0K5C1b4hayu017ozFIJ8KgLX7AqPRp8ToIi1j0DQzT?= =?us-ascii?Q?6QGyJ6Vv5PE2ScNx4g5XlU1ZIPmHZ6D8s55ekCKohlo1r6Ctnm7p33iyLtiI?= =?us-ascii?Q?rExu8rZDDix+0HfHeP+ZlMVB6Uw/O2kar46BFnQRUFsr0mH9fgLNJj0+gE0E?= =?us-ascii?Q?+bsqug7Tj7w4s9N8xEN6X7f42NmQlXn8fL4Zc6fdqDaJb2A8V4LcLKNR5iRb?= =?us-ascii?Q?GZhtvhnN2GTdpE5ljxRtTx98mF6TaI0H7pnOAwNvCwah9x4NhwzUvcPZR2ZJ?= =?us-ascii?Q?SXbpHE5lPlA1QaPn0e97Xa3OCUOsQXJ07Yx06U6UtNnk5ecvIlhTKgQ4nA45?= =?us-ascii?Q?fCLPsVN8Skx9hfwXe3rC1xg+vFoQ7qlJozn9u2/nucLHk/uPmzibGiTrj+UJ?= =?us-ascii?Q?Ts8mhgkOFL15s7WRYkrlhECwDtXm9WSUAIRs61DAgCvWOleu4ljuzIWWGQdR?= =?us-ascii?Q?Jlq4fqyowzasIgJ/Sq2EFXXUUQ1VQTitHGCCqS2IurqA2cM/xWLuyo0Jk/GU?= =?us-ascii?Q?7+9iYQ7vZTur8E4aIRnjNP1mykQ2WQAVQFwmQ7XsDDPDxLLR4ZG4nt4g/gg6?= =?us-ascii?Q?2Sl6S+61tF1mFQnRU5BZyUPFiI4WV7abDy0wRC0jCN/kXFzI3zXQACZ/fKED?= =?us-ascii?Q?As8FJwOzVygoAE9O2P75iFJ4dNkhvVKtz74CPUBGGlj+ofgag7PonGz0Uhl6?= =?us-ascii?Q?14ZDcJtgA4jwrvKeuWkd3B2ZZpPwCyy9+0q7ZXIbLdmAjDoy5l/jQpVPGbsQ?= =?us-ascii?Q?t0yX2jhNgLXfi6RBU9tl7RjYVFFyDmMRdxbHo2MLocTa2s4BMY7P0rTh/+9a?= =?us-ascii?Q?MLYUDW0Kt8lJz4jv/6i2aPLblfofE8SsFRcDACd7pWE0daOM8Vihggp+OY2i?= =?us-ascii?Q?+9IhiYhuFQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cac42666-0a01-4211-f642-08defc54d96f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Aug 2026 11:44:08.9765 (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: 5QGIMO8WuAHBXowJFRsx3vrGZFfR2uZLC7mmAYMt40uENLDjpnRzSu8wx+xUdZkC X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB8117 On Mon, Aug 17, 2026 at 11:16:17AM +0000, Pranjal Shrivastava wrote: > But, regarding PCI P2PDMA, you can still enable it with ACS enabled in > the upstream kernel *IF* your hardware supports TLP forwarding between > root ports. > > When ACS is enabled, all TLPs get forwarded to the host's Root Ports > instead of getting routed directly through the switch. Generally nobody wants to run like that, the performance is terrible. The reason these systems have a PCI switch is because of performance of the P2P path. Jason