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That is to say, it seems that there is no need to > expose "tasks" under ctrl1. Should we hide "tasks" for the kernel group? Please > correct me if I misunderstood. No, I don't think we should hide the tasks interface here. It provides the option to use a group in a mixed mode. # mkdir ctrl1 # cd ctrl1 # echo "1,2,3" > tasks At this point, PIDs 1, 2, and 3 will use the schemata from ctrl1, regardless of which CPU they are running on. They will use the same limits in both user and kernel mode. # echo "assign_global_enable_per_cpu:ctrl=assign;mon=inherit;group=ctrl1//" \ > info/kernel_mode After this, all CPUs in the system will use the schemata from ctrl1 while running in kernel mode, including when executing on behalf of PIDs 1, 2, and 3. Essentially, this provides the flexibility to run in a mixed mode. Thanks Babu