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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?jupny+855fGhers1LgpA2GHaHexu7BNbnXKNUdI3e+dIPWsewUKeGJgq5uOY?= =?us-ascii?Q?BLsOFnW9zrsYRKd5V95ZQwRdpzXsj9sUdMl1I35utmcWm4yUco68d3HTRv7V?= =?us-ascii?Q?gD0PXeR6VBESsP+Iu58M45R7JAbpzgiGX5ustXM/ij3O7yKzPbX9YtpS0Fdk?= =?us-ascii?Q?DQbC4m0zLpKWLx9x2mkKfa4GR41p4Zu5L849mQ+bTHEKggAof07TMY5Absm4?= =?us-ascii?Q?xj1T3QEfleBMZpvcb3hLxVTME3FWCHYRVwrvhIKcPTlV6qV27CtGsjIap1Zi?= =?us-ascii?Q?6p2mD43IYBuu8kIgca9f1tfrV3xnZxwA8RcbMb9PdVOEnaay3nHJt6hNxZd+?= =?us-ascii?Q?i05y+1Y6NNNKNEFCv74WXCjduDj0ElmrqJZbc77pKOUNvzabngg8CC9M/GBl?= =?us-ascii?Q?CwBP9scFdqhrg4liVVxamWvpb37erwmywB8EPThgAnO2STwi8i5lfbzI7doA?= =?us-ascii?Q?tlFaq1WUi9ZH/QTJxc6lVWfWhV93PYntJuj7SfC+jXAvVw2SQpoXjTxSZMDg?= =?us-ascii?Q?uRTXoqNAMIIffgSDWEQaJDQE3Ft/AuchwH2LWYiP4sunZc4cgG8xmDR0EcFT?= =?us-ascii?Q?200lR4QCaeibFd+I0dQaNa5i85iqroC57kA9jVHbK0KPCg+nspr2TDZtgHR4?= =?us-ascii?Q?Wv4GY60nMtmCxxBpOklHoVykYhEOFJEO7LVvBRxZ+xESP9GsXRIBhOBd9sPN?= =?us-ascii?Q?M/WWylUI0yh+zryMGg8zUBL2qAguev5tWKn30zSYY4yAIyuHwlZSUpeApdk8?= =?us-ascii?Q?xDV02ZkbhCrb5pJLC5z8fGm5GapFaQ8Rh3yIDeY0Qbyn5Hg20srk/xa1D+97?= =?us-ascii?Q?fUpbX5AbOz3pOabW6xGZFhE4y6raYJ6C72DfCBDgdM4yx2lQtzAXvaAjX/x/?= =?us-ascii?Q?jeh7BTby0n162ZS9qRC8jrkPdL4xN3W41X8hD4mhEXcxTE94yrzA6dJ0yEGh?= =?us-ascii?Q?BK9OuPX2bbGFZt41O1w6E71G9VYa1QFPO1jc6L2M24k7p6W1ZVSEl3hDKX4j?= =?us-ascii?Q?XlNWniDXFycUutX1WHBNZro/xeKIiJa7mHjulTsDsH//UiVMvvCCjZFuEY+c?= =?us-ascii?Q?izncZOoU/H7hOPfoOGkGvU1kcAUxYJlNKnMNWDBpPrX3M+/eg1LHsZdy9S5/?= =?us-ascii?Q?BdbLxK6y/U0ZdXb/RK0ouo+oyN+zQ82Dm7FiX1atsVMtaek/8PHAoXcAO4je?= =?us-ascii?Q?vxy5i6iGzw94ZSU0sFtQVEn/giU7pFUbBEAkcRSgzZx4XeUG5mw1YmC4NcxO?= =?us-ascii?Q?RyPElcUDZ7P+9eZDxfaVi5BLN+dXk9joLIK46GNyqQbxwlvBo47c/7QTJ2mh?= =?us-ascii?Q?C0zZmkyRe5vkx9NITNhq3JsKSTcZdBH6F5O7qAkAcgL3SvJMm1lZGU9aiCmD?= =?us-ascii?Q?5Ooy+33/qECJEUcYaukHC+xyqOi8b0zNFCXlTvQT8sLHlaB1/dI69QZuFKGJ?= =?us-ascii?Q?Fwzx0oRg+mrDQRi+w6V8hb6S7ikb+bdJsKijLcd2a5woNLGhoXSIEIXgB7mD?= =?us-ascii?Q?bHN3D+p3gilP3ipGXvfDhEIDzjApQfvDA09TPhckqh1cGH22LpyGDMxGxi52?= =?us-ascii?Q?VSG/YjzZB8XorTY1RuwzgiFM7mZcqCYHhGPuD5aAjlm3Nb79CGNfvvgV/Xdn?= =?us-ascii?Q?T2aTPuiSmLhpsGUd/SXa2egLYN3nOLuGKJIkKxvQM5kjvq0HshqgogsNB2Sk?= =?us-ascii?Q?2454Vwn7nOmG+czgXz86CNHNS+PhgWw1rfos5Q26lec/mfIMQ1Or4xqe6CE2?= =?us-ascii?Q?+ZgH+H9b2Il7zaxmCJlafqS07cZkPc4=3D?= X-OriginatorOrg: santannapisa.it X-MS-Exchange-CrossTenant-Network-Message-Id: 16dcb79e-295f-4bc9-941d-08deaf414994 X-MS-Exchange-CrossTenant-AuthSource: PAVPR03MB8969.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 May 2026 09:40:08.0432 (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: GUcIdr7J/j618y5hFNRcUczHGobcreZscecDUnSAxpzUo1mbU+WannaltdAhSv2E+pjDVmrIwZ8lr3YZoP3mTEYhjxo8RT39OKsg6sNUPeo= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB9PR03MB7260 Hi all, On Thu, 7 May 2026 12:53:31 +0200 Peter Zijlstra wrote: [...] > > - This has the same problem with cgroup1's rt cgroup sched support > > where there is no way to have a permissive default configuration, > > which means that users who don't really care about distributing rt > > shares hierarchically would get blocked from running rt processes > > by default, which basically forces distros to disable rt cgroup > > sched support. This is not new but it'd be a shame to put in all > > the work and the end result is that most people don't even have > > access to the feature. > > Right, but cgroup-v2 allows enabling/disabling specific controllers > for a (sub)-hierarchy, right? So if the controller is not enabled (by > default), it will fall back to putting the tasks in whatever parent > does have it on, and by default the root group would have and would > accept tasks. We are discussing this issue with Yuri, and we have a doubt: if we disable the RT-CPU controller for a cgroup, would it be possible to enable it for its children? (In other words: if we want the RT-CPU controller to be enabled for some "leaf" cgroups, we need to enable it for their parents, right?) Thanks, Luca