> When a CPU is kicked to do nohz idle balancing, it wakes up to do load > balancing on itself, followed by load balancing on behalf of idle CPUs. > But it may end up with load after the load balancing attempt on itself. > This aborts nohz idle balancing. As a result several idle CPUs are left > without tasks till such a time that an ILB CPU finds it unfavorable to > pull tasks upon itself. This delays spreading of load across idle CPUs > and worse, clutters only a few CPUs with tasks. >
[..... snipped .... ] > Fix this, by checking if a CPU was woken up to do nohz idle load > balancing, before it does load balancing upon itself. This way we allow > idle CPUs across the system to do load balancing which results in > quicker spread of load, instead of performing load balancing within the > local sched domain hierarchy of the ILB CPU alone under circumstances > such as above. > > Signed-off-by: Preeti U Murthy <pre...@linux.vnet.ibm.com> > --- Looks good to me. Reviewed-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
