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Sun, 15 Oct 2023 08:46:39 -0700 (PDT) On 2023-10-12 at 16:36:26 -0400, Mathieu Desnoyers wrote: > Introduce the WAKEUP_BIAS_PREV_IDLE scheduler feature to reduce the > task migration rate. > > For scenarios where the system is under-utilized (CPUs are partly idle), > eliminate frequent task migrations from almost idle CPU to completely > idle CPUs by introducing a bias towards the previous CPU if it is idle > or almost idle in select_idle_sibling(). Use 1% of the CPU capacity > of the previously used CPU as CPU utilization "almost idle" cutoff. > > + > +/* > + * A runqueue is considered almost idle if: > + * > + * cpu_util_without(cpu, p) / 1024 <= 1% * capacity_of(cpu) util_avg is in the range [0:1024], thus cpu_util_without(cpu, p) / 1024 is <= 1, and 1% * cap is 10, so 1 <= 10 is always true. I suppose you want to compare: (cpu_util_without(cpu, p) / capacity_orig_of(cpu)) <= 1% -> cpu_util_without(cpu, p) * 100 <= capacity_orig_of(cpu) ? thanks, Chenyu