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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?BMBamTnTaCD44RwxIFNLh0uocq21pZqlDFnSSSMUeLac7P4K2Xs9hnNIkXIM?= =?us-ascii?Q?t4kI3T5xnbUxXap3JBz0NBfIEl2XmFUtB8m7BHMpvB8hdCg7xPOQH8U87Lfp?= =?us-ascii?Q?U2WZ5okyejiW/ZG+YvNK5SfWvhfb+8bb2dakPbnnPRcjwWgO1qNyvH+m3aKp?= =?us-ascii?Q?3zrpltFQAr0i3sZ7BgPzxfrV/ILZIurdXmIeQGkHfDrzhuhC0VwXLF2O7GEB?= =?us-ascii?Q?jnliYZrhRD7hgKKeBswweJSgGVn3jWlnqwwVHGWXZSfWxwUyAQVQlTtmHZLB?= =?us-ascii?Q?NHHcct7BL7YiUuuDqozRm0XlWRdoRgd5nDN7SHPB/IUWws53XGmQu2R/wJtr?= =?us-ascii?Q?LmJXNcs15VQ2YIcLaCJRPhTRER6FRWpHuyjo8qvj/9Gp6gQdGt8F4VslL51Q?= =?us-ascii?Q?rJ4RQNIzUcTL+fodLUPQAneHBV2GLxbUYvq8O2JwK54t5IYhMuhbqtEXrwUg?= =?us-ascii?Q?pTxtBxWgao4CF493/SLtyMdfvghPbvO2QHemc+fPv1R/46yPb3R1hiNBzOg2?= =?us-ascii?Q?FU8yZ9bgHQcR8DrRFy4oc1OtfIP6c4+ab15JYIS2cBq9z1htW8irN2HYnW8q?= =?us-ascii?Q?3DG1ejtHwJyHwgCZEsGtOEfgSrFT8CHTMLQLuNVTtt+s4wC76pIDBgc2zjHE?= =?us-ascii?Q?04lw9WGBgnWohGFCy3CEjyfL6q/TFMSQLgeVsDgQLHsiymvgVktvhogC12jY?= =?us-ascii?Q?EBjaYT3lU4fLe0rbBR26Cq9tplEhpJYh3yEDVxTCwuJVQ4X2DxUZtjcly1TA?= =?us-ascii?Q?YFBs5PxEJEzTNGHVEk+LXH0k5lPoEZEOsG59/MHa3gOjFA23vNVRxjqKPxHq?= =?us-ascii?Q?vUbuE1NYjsejB5XQ7zrf5AcMnDpTDOOTX8g6UWFKrQS8UTZMO1V1nvGwbEHq?= =?us-ascii?Q?4QieWEdxs9ZoT4QQX9LQXzpFPhhOcV4fQA237i2gOR2hUgEEkwc4BSOelpVv?= =?us-ascii?Q?PpbukAlNogDpwcGo6Cgp1k4nqtTF+A7tuTWsTpqoUlPCmvqh25t+52RPumgY?= =?us-ascii?Q?v14UrZLh4SJeupMook5azOl3CQzlAI0Xj3RwDh28fe35Fea1dPbO+BEEs//F?= =?us-ascii?Q?srvXXxXAQ7FIKtliajfWLYF0mrHY4EvyPd1z0/D3GuWSvKKam9XuEJ8um4oe?= =?us-ascii?Q?XtSA6hT8F2VmQTzMgi7cHWDhMu/xCgYHH22yk+sNLP0MiGlfXX9ifFJzOPrA?= =?us-ascii?Q?TjoBh1hHNhaI7FcoowLks5mVVJtHRmn9tFQSDnydGKUqFGs5FOmf9ZQQZPbR?= =?us-ascii?Q?NdQTFR43Oq9XnrtbS//b8KMrdaxTdGGMqT6ErmuK+TZTMuRGKTbNo6Xq5rnw?= =?us-ascii?Q?Jhnl0eMLfCYpghQIvUFtkHvBK9ySNtpx9k5gKoGtF8AUZmzGgT6TZ8bVDMRq?= =?us-ascii?Q?3H3zMQ6KczpZA7QNI8wy517jt2z4HpNS8hIH/ayGYAdDRh5XLxnNh6GiqEw4?= =?us-ascii?Q?hvagJEUdOBAxM7SNXATfT543jD9Ny5zK/8sXc30+I8pLQeBpe1qEhy6gNqBp?= =?us-ascii?Q?WxgaKgHM9wRM1+0Z28srlfhHDz7ECnei85A0nDLCUbwqYcAQ7pDPjcgr+iQE?= =?us-ascii?Q?PrI1ZzCGa/LMrHKY4Zfq/TzC8NgUCOs2w5Nc6Lu7?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e7f4195f-b473-4de6-4863-08dad8ad9286 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Dec 2022 23:48:42.7280 (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: rsoD1w+AF2V8sxx90yk/L5ER9y8gcKaDyQhgjq97Ng8cgOiOcYVE3qc/sRMW01wR X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5112 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Fri, Nov 25, 2022 at 09:00:26AM +0800, Chao Leng wrote: > The ack timeout retransmission time is affected by the following two > factors: one is packet life time, another is the HCA processing time. > Now the default packet lifetime(CMA_IBOE_PACKET_LIFETIME) is 18. > That means the minimum ack timeout is 2 seconds(2^(18+1)*4us=2.097seconds). > The packet lifetime means the maximum transmission time of packets > on the network, 2 seconds is too long. > Assume the network is a clos topology with three layers, every packet > will pass through five hops of switches. Assume the buffer of every > switch is 128MB and the port transmission rate is 25 Gbit/s, > the maximum transmission time of the packet is 200ms(128MB*5/25Gbit/s). > Add double redundancy, it is less than 500ms. > So change the CMA_IBOE_PACKET_LIFETIME to 16, > the maximum transmission time of the packet will be about 500+ms, > it is long enough. > > Signed-off-by: Chao Leng > --- > drivers/infiniband/core/cma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Applied to for-next, thanks Jason