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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?HC8bPS7F1uZ+sncUgZDq26UDeUtvjr8x7MdP8jBxU9bTtDKHFsdxmzn6RIn2?= =?us-ascii?Q?jN/5/GC15n1YpQdVTfM5YrA+HHvXTcLRdFse+4iWx2O8ymoc97cEDK/hsxvL?= =?us-ascii?Q?pTAfgiS7jwBdbuQ8KwL61bSRlLSn0pPeKB0zRj3MHFpWv2dUGlnW0vndOgA4?= =?us-ascii?Q?f/qYnrD+YDjEVGDdo3Dp0Oca8MJwwVNCe5TWSEgqtO71KCObIaQ5rXawG32J?= =?us-ascii?Q?K0RA/3rJANwT6mBGovNH02OEl28DRzUtmHzyUBUCJozK2shdUVm8tj2b36od?= =?us-ascii?Q?3sjxQafK8aCS227AklqYSUDUCp+WSPF91N5dfuBEEoNT3il6T+ihTomZvjhr?= =?us-ascii?Q?QypTs1qOcs8GcsNdfx7sXqRQBLVJoOtNcbcUI+HrFw+SX+4H+Ehs1oslSPTy?= =?us-ascii?Q?2kBL2ofYz3/sZB9+XEFP4ge1YYRpJKxjdLkvJI5mdsi1vpvCwWPd+pcP1hDo?= =?us-ascii?Q?LjeKqVdVPdbevjx9tlTmIXGEJJtR4EueSVW8vrPvj5K8bZCv1qgKlBs9t26J?= =?us-ascii?Q?RnrHQq8dQtsR62qhE7jlGi9nDXn8m939NttvSjyFnrzL39zjOhPhtBwCb2Ge?= =?us-ascii?Q?ysMs5q94jL8nXAdC+7dVL772ptd9dsKaxU8YC11m0ZrT3wgSdjvM5je9VDxR?= =?us-ascii?Q?qPvDdqEJc7sET3/cHt6s14w0rkV6UWGUU9xoUzx0p0XsCLLlaimURL5ckkP5?= =?us-ascii?Q?+YZ7oNM8nknVw+2wNzC78+KQU0F+o7h4pJJXTEOlVYsut3/MAdu4/p2kLxvq?= =?us-ascii?Q?Rp59oHpAfV3FRgqjGjIeB7fZ7QQuWuUAs0GGnKg8pI5dDScf+rF6EPKeN0VH?= =?us-ascii?Q?crUOr08i0oLweKmsH5bm2b74Mw3rrM4si8Ko4CBrOYmrBIG9LEXG958ZCHZz?= =?us-ascii?Q?aiCALSkKrDq0UFI12HbOzPi3TROtX6QEvbWze+dEfpY34v0BNTTHkb9apR2U?= =?us-ascii?Q?0LUkihciiTOM7Iw1l+2JfiNx6dk8x+5VT4uiCtXW/h0ksUI/df9cCCgXk9QP?= =?us-ascii?Q?ZLpkJnrkSJs0RgH1uP4yqNB+ka44YrtVIeQRdrG5SoKG2HEFinKOtNd421YQ?= =?us-ascii?Q?xTqZPKz16pPfUZeBc/rFwjvpM+dlIXT+jxgEg4AZly8bGr41Iu13E2ykhOIG?= =?us-ascii?Q?9SGNpz0RwbpI7DVylom7ev+jmXj3PbfCQDEcXOJFjFuL7HyP1pd0IF057+vk?= =?us-ascii?Q?0Oes0l/iRHzbwdB3v+5WpOZikVyFSvxpa+c1hRXUilDA7NLSBiVf5JaSZkRT?= =?us-ascii?Q?1INrRb1Gh712C1qAWrwhnx6KjbGm4HLtcutubNJCqT4oR69b2A55cvrSR50+?= =?us-ascii?Q?8f0M+Zy/HN3Jdzrdqgm5lj0laZvibmvmaXw0zqTIPPpldZ8vXzYrb1HStz/k?= =?us-ascii?Q?9Z0paFrCvmRZtdnj0b3OTLcyNywYiT2o3Fv7cVwpbuzyZzIBTZNFRmFEhK+t?= =?us-ascii?Q?ZjVG0+gsP+v1cUSpNB5/LD66RYhz6E3rl+LSPImzrhIv9vUUNtW5L/vdfPyh?= =?us-ascii?Q?MQ94Ty9FhlwlcSwXUY+ncx5CEtG2RgLWa2Y10LN3L3sQfYTyw9ByOdBmFOKd?= =?us-ascii?Q?Dv91rjBnk38X/O5RcfDMqHHgLoJvCk8Z9hiBIveK?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c118a827-12b7-481a-47f5-08db669c53dd X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Jun 2023 14:43:01.2648 (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: NQOFlUkyCkWAkN3eCOuoC+PWvO5NXmiDYiag7vE7GUEvfjVrH3jNVln7O9iVBW1I X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB8538 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, May 25, 2023 at 03:03:54AM +0000, Liu, Yi L wrote: > vIOMMU may introduce some performance deduction if there > are frequent map/unmap. DPDK doesn't do that. And once you turn on the HW IOMMU you negate alot of the micro performance wins of bypassing. Maybe there is still some argument about giant/huge pages or something. > without vIOMMU is supposed to be more robust. But I'm not > sure if the noiommu userspace will adapt to cdev noiommu. > Perhaps yes if group may be deprecated in future. I think that is more a distro question, and we don't have to answer it fully now. Jason