On 2019/4/23 下午4:44, Peter Zijlstra wrote: > On Mon, Apr 22, 2019 at 10:11:24AM +0800, 王贇 wrote: >> +#ifdef CONFIG_NUMA_BALANCING >> + >> +enum memcg_numa_locality_interval { >> + PERCENT_0_9, >> + PERCENT_10_19, >> + PERCENT_20_29, >> + PERCENT_30_39, >> + PERCENT_40_49, >> + PERCENT_50_59, >> + PERCENT_60_69, >> + PERCENT_70_79, >> + PERCENT_80_89, >> + PERCENT_90_100, >> + NR_NL_INTERVAL, >> +}; >> + >> +struct memcg_stat_numa { >> + u64 locality[NR_NL_INTERVAL]; >> +}; > If you make that 8 it fits a single cacheline. Do you really need the > additional resolution? If so, then 16 would be the next logical amount > of buckets. 10 otoh makes no sense what so ever. Thanks for point out :-) not have to be 10, I think we can save first two and make it PERCENT_0_29, already wrong enough if it drops below 30% and it's helpless to know detail changes in this section. Regards, Michael Wang >