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However, when those CPUs belong to SMT cores, > > > > > > Interesting, which kind of system has both SMT and SD_ASYM_CPUCAPACITY > > > ? I thought both were never set simultaneously and SD_ASYM_PACKING was > > > used for system involving SMT like x86 > > > > It's an NVIDIA platform (not publicly available yet), where the firmware > > exposes different CPU capacities and has SMT enabled, so both > > SD_ASYM_CPUCAPACITY and SMT are present. I'm not sure whether the final > > firmware release will keep this exact configuration (there's a good chance > > it will), so I'm targeting it to be prepared. > > That's probably not the only place where SD_ASYM_CPUCAPACITY will fail > with SMT. The misfit is another place as an example Yeah, that's right, with SD_ASYM_CPUCAPACITY + SMT when a misfit task is moved from a "small" CPU to a "big" CPU, if the big CPU has a busy sibling, its effective capacity is much lower than its nominal capacity. Maybe when SMT is active, we could allow pulling a misfit task only when dst_cpu is on a fully idle core. That's a simple change, I'll run some tests with this, but as you said there might be other places to fix as well. Thanks, -Andrea