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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?YmlMZm9neEx5TjVWMWsxaEp2RlhoZm53NmVwalpUNm1IT21PTW5TSnNESlNZ?= =?utf-8?B?VlpzM0RWT1I4eHI5Mzl5NzJIWGZVNWhaMm1GWENKNER0cER3bytiQlFwNkVu?= =?utf-8?B?ZWljNFEveWRIR0V4OVBJc3lPcTdrM2YrZ0Z6NmR0RXVuQ1Z4eUw1TXp3dS9q?= =?utf-8?B?eTVTbzV5L2s3VWloZnNYU203cjZtdHBtYWo1cG9STFB1bGtYN1p0YlV2R0dp?= =?utf-8?B?ZnNVNkpnZXZLZzNyQzZ1OUEwT0J3aXlKK3ZSWEhFSzJQV3RLMi90YXRuazha?= =?utf-8?B?UC81YnltQ2JWSFpqQ3BmRGE4d0xheko3UzRCRmtwN1JJVGpqOTZmWXBtbkRV?= =?utf-8?B?RGRDYVg5ZkREVG8ySzM2TVVIL1N5dXJscUhwQUpQNjc2UEUrUFZKcDJOZ21C?= =?utf-8?B?OXNvZFl3WDdOeU13aERLL3d4SUU5amJOamlMTGRQWUsyc2xIZFB5MDU0SUI3?= =?utf-8?B?TGM0VHRWZmcwOGg3VWJ0Ykk5bHRGVGtma0VLZ3NJeUtiNlVmQ056QSszNGVV?= =?utf-8?B?UEJmRG5jRS9SNDFseHUvcnJwNzVZUW1Td0Urb25STCsvK2VYYWd4enZZQ2dS?= =?utf-8?B?OWFyZlRVNWpkVUQ5WXRwSjZSczNiRW9mbTBza2RwSlRGWWI3QklCb2pxdkRT?= =?utf-8?B?cmtOY0xBdVlqYWkvMXYxVXZnUzhvQzlwSlNHL2FpdkVXck1GQ2gwTFM3VlJo?= =?utf-8?B?a2dscGxwaHEvbjUxYWR3T1BCSVZXYUI2Ynh0SUtBZHpnbjQvUEpmVmswRnds?= =?utf-8?B?Vkd6WTgxejlGSEpxTjV0MlJERkFZWEc0SWhIYUxxY0NRUzBQNWxXbnJOaU5S?= =?utf-8?B?Z2tHVU1ZWk9kSDcrNjQxUzJJaEcxeUYvVmcyY3EydUFPVHFNWjNFZkk4eGhs?= =?utf-8?B?Q01RcGtKbDJNcndDZEtNNjVtUElhRG1UVWdvcmcyYzlQRkRPUGNnZGVjNE9Z?= =?utf-8?B?UlBrejh5MXhRYjF3ZksyK1NqQ0dzTlRnRDVHaGZpRGhhTGw3SDdnNGI1TG9O?= =?utf-8?B?cUZsVi9HUGI3Z1YxeWFlRXFzSk1IWURwbUJGQk1RbktCWkVWbUNpMEI5dlRB?= =?utf-8?B?QUZYVE9na1c5YXgrTW5ReEFvMktjSTBDbWMrRFJmREpPTUdETUFyRG9DQXpT?= =?utf-8?B?Tk9MMzhHRWVQQ2lXMXRVSnMrbDFDTVkwNmgxcHk1MTliaUJYeUJFTW9iTmNs?= =?utf-8?B?eVJ0dkZSZTMxK0NDWnJnUUowT0ZobVZ1Z0FEanA2MCs3TzRNT2d2NjY2RTZP?= =?utf-8?B?bEJ0VWttbW40Si9VSkp1amYxdWNIdEwydHhJQkxJSENPYWh2SGxmNFdOcEdD?= =?utf-8?B?dVB6Sk1ZM1I4elpuZ3BaL1U0QmhMenA2WC80cG1lTVZwRjl1VTdqWnM2SFB0?= =?utf-8?B?SXljbzBnZURWemJ2NG9weXlsTFh0dm5odDIxUjh0WGU4dlFCVTFjUHMvcFpo?= =?utf-8?B?TEJQaFZjdEJhMEZiNWI5d3laL2ZqNUhVR1pEcEhMYnk1dlY0U0czNEhwZm15?= =?utf-8?B?ZGZaaWRmckM2ajhEU3FreXBOdFhWc3RSbWk0b0xsSE5acElBN0hVdUlxOGhx?= =?utf-8?B?eTNQUlhHQjVDeEVYQUIxU2RpU2NQcFJIYWhrcUxSeFV0eUxxWmlka3NvWjNU?= =?utf-8?B?WHoyaFpKUWY2VFN4RFFXdUJpUUh6eGpVM2FOeXNOdUFFTWowMUc2VGdudzNh?= =?utf-8?B?elZqSGdSOGJVRW91V0lhSi9nVDlsMlFlZ1pRVDczeC93VnNrLzBvclVteW9s?= =?utf-8?Q?IZL/Z3uF5lR6ip8m23SszfBEmLpJyDyMw1LDBK5?= X-OriginatorOrg: oss.nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: c708460b-934f-45a7-936c-08d98a2b354a X-MS-Exchange-CrossTenant-AuthSource: VI1PR0401MB2671.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Oct 2021 07:14:03.5570 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: AzzIhMow2gWtC7D7IHEcme1HXdd927nfOwGho9o6RTwWcXB6lmR1eDIPb6vZfi2WSRdaHkidk29kkyLq6NgE3UiipCKg7U5Y1PinvCgCukw= X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB6799 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 2021-10-07 at 13:19 -0700, Richard Cochran wrote: > On Thu, Oct 07, 2021 at 03:31:43PM +0200, Sebastien Laveze wrote: > > For example: > > Let's take a worst case, the PHC is adjusted every 10 ms, vclock every > > 1 sec with 1 ppm error. > > You can't justify adjusting the HW clock and the vclocks > asynchronously with a single, isolated example. This was a single worst case example, many asynchronous PHC adjustments impacting vclocks. > If two independent processes are both adjusting a clock concurrently, > asynchronously, and at different control rates, the result will be > chaos. This is especially what we want to prove feasible and we think it's posssible with the following conditions: -limited frequency adjustments -offset adjustment in software > It does not matter that it *might* work for some random setup of > yours. > > The kernel has to function correctly in general, not just in some > special circumstances. Of course, so what tests and measurements can we bring on the table to convince you that it doesn't lead to chaos ? Thanks, Sebastien