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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?PMPPzqgBdn9m6bghK4DqSHpLbiOdq0F42RlW6HoTz9qXMvYNVKUoBac2cK2b?= =?us-ascii?Q?mAzTHhSgb3N/ORMIVNPlYaNw0+/KX/tFMlNiTAtNwKXWQyd/NqUIu6dcw9cT?= =?us-ascii?Q?3kTgRX4x3UY+SrnilLEGN58hgLClua9U140Cweglapds9jeE1Tp5M5pNklgx?= =?us-ascii?Q?iBP0DWpT8lm0Rf6sJgJRO/DocpGW1Dx0UaZ9+xlRbf8bb+hNUilo+NoGBFJM?= =?us-ascii?Q?rUOXljgsjIBmvT7tJ9iRYqMxojzWu42Fz1/VbTnTgOHgf+pC9DdHVbo+NFW4?= =?us-ascii?Q?0A3Hq4GkwTJuN6UGduK+ZgRt3wlMJOt+b58s4C/BlAvjaJqgdN6ixvdSiOPv?= =?us-ascii?Q?vEnDidcHtGVGLLpCzXtkaVZNFvAcpeC7qpjuDI22p3wpDtrS3infFNffJiKC?= =?us-ascii?Q?HJXiYgW85B/HpEEPHkBrREfzIiRsbR42pSH4C6iuo0f0a54Hu7PuPkdp6RRk?= =?us-ascii?Q?VLAq1BspgYifvfDS3xGY05QLHHEQ5xzWDVsUnvQEnBgeP+f80Fm9P8eIL4cw?= =?us-ascii?Q?QO7iYGVxiDUmI9psYpaYnxl3BCCGSoh0oNV2bSyoCweFkdbKLEue0pWFElVX?= =?us-ascii?Q?93QU4Xdwy13zfCmptXRhNs2Y1aDmZ4CdqolJP5drU47Ndu/AXQ4du56HNk56?= =?us-ascii?Q?Og9fVki5n88/c69/FEOEJMd4GcvTgdZhAHsAh6oWOTARLAUCPtNChTMC9TKi?= =?us-ascii?Q?nUnSaC/cvH2rxVSlqwktQJzJNn/eQYvAl4kP8fTvi56RHGjTeCNkj8kyaoQg?= =?us-ascii?Q?G1TmFVgVmiiP7N0WEY8eT8ILAsD0nzzr81MRxGtTnPD17EO0+bHG9r52QGWk?= =?us-ascii?Q?VXuEIByPAQQlQi/JeGjFPSjDX6H62uw/xFEQrd+QdRDzJVzlwGD6ciKZhre2?= =?us-ascii?Q?iyroeIptXVi1JUKNS15+t3VoSNm6jwh4xaw1xrmmCGhHuvZU9j0niQBq+1VK?= =?us-ascii?Q?2KX/dwA3kqSRPkPADw2ljMgll7+u6e1JB+0OqutPnqVYCMJWPh0zmDrVshPe?= =?us-ascii?Q?b0Jma+rj16BvMxtjPc0euGs9BT8J8RmiZkVOvtYhr6/YX05KIySdk1Hn1OlC?= =?us-ascii?Q?tho0XW8PbvsCtSZgAhXCniNDJ/9ShK1fePtEBFY4zIyC6dFZAV81fLY4I98R?= =?us-ascii?Q?YJIn8zoIx4XMlgSr+/ssTtR/Szm41Oaam6aEyBlJuPg9G3QEMe7X2nDnvxWn?= =?us-ascii?Q?pI5Njizse0fvndL3REAQ9Sx7fBKvPmMnIvFVIBuTPPm+TVbEy1Em67L19HFj?= =?us-ascii?Q?CsYLB08URo82MW43MG/QCDeIJqgot5qHQQbttePwvvEmxkVCCjqex1uzdM2C?= =?us-ascii?Q?xTmh4oT+fXN8hZF6zOKwawN4a1ZeJkPsR9TNoyWUQagMZC7cP9O69DC8/ap+?= =?us-ascii?Q?8vSxkbkfzb8yIwZNUeKBER/GfuR57gU0RwQ8i4bpr3I7uXz3NSKYauFCGHCI?= =?us-ascii?Q?yFhniv2DgeFmqmNlb15DxJ2GmDigvIWPhzrHIeCclByJMD1trgmpDDSCCCoc?= =?us-ascii?Q?t9puPD6eTq7JkYTuzi86B133sTHF8gbZyVWoFcf5CIOYn9T/HGM5shm1BlUR?= =?us-ascii?Q?zcdz1bwQwcVB83zeYp90MvgWMuWewc6+zr31XH80Bs07iGT9uwmURqGtSxG3?= =?us-ascii?Q?uA=3D=3D?= X-OriginatorOrg: santannapisa.it X-MS-Exchange-CrossTenant-Network-Message-Id: e92d3004-fa2b-4a04-7bd5-08ddb32424a6 X-MS-Exchange-CrossTenant-AuthSource: PAVPR03MB8969.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Jun 2025 13:36:37.3874 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: d97360e3-138d-4b5f-956f-a646c364a01e X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 4Sm8NwpCQzk0avtfOudU4IrmvtKHpESeMyAX8lmjpOeuV9db/IxefgoECBf3I2U9FktmBVpu6WgOVKL3AwWgknk3lGsWry8/4jg6gosmjTA= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PA4PR03MB6752 On Fri, 20 Jun 2025 18:52:48 +0200 luca abeni wrote: [...] > > > should be decreased by Ui when a task with utilization Ui > > > becomes SCHED_DEADLINE (and increased by Ui when the > > > SCHED_DEADLINE task terminates or changes scheduling policy). > > > Since this value is per_core, Ui is divided by the number of > > > cores in the root domain... From what you write, I guess extra_bw > > > is not correctly initialized/updated when a new root domain is > > > created? > > > > It looks like so yeah. After boot and when domains are dinamically > > created. But, I am still not 100%, I only see weird numbers that I > > struggle to relate with what you say above. :) > > BTW, when running some tests on different machines I think I found out > that 6.11 does not exhibit this issue (this needs to be confirmed, I > am working on reproducing the test with different kernels on the same > machine) > > If I manage to reproduce this result, I think I can run a bisect to > the commit introducing the issue (git is telling me that I'll need > about 15 tests :) > So, stay tuned... It took more than I expected, but I think I found the guilty commit... It seems to be [5f6bd380c7bdbe10f7b4e8ddcceed60ce0714c6d] sched/rt: Remove default bandwidth control Starting from this commit, I can reproduce the issue, but if I test the previous commit (c8a85394cfdb4696b4e2f8a0f3066a1c921af426 sched/core: Fix picking of tasks for core scheduling with DL server) the issue disappears. Maybe this information can help in better understanding the problem :) Luca > > > > All this information is probably not properly documented... > > > Should I improve the description in > > > Documentation/scheduler/sched-deadline.rst or do you prefer some > > > comments in kernel/sched/deadline.c? (or .h?) > > > > I think ideally both. sched-deadline.rst should probably contain the > > whole picture with more information and .c/.h the condendensed > > version. > > OK, I'll try to do this in next week > > > Thanks, > Luca