Re: [RFC PATCH 1/5] numa: introduce per-cgroup numa balancing locality, statistic

From: çè
Date: Tue Apr 23 2019 - 05:14:59 EST


On 2019/4/23 äå4:44, Peter Zijlstra wrote:
> On Mon, Apr 22, 2019 at 10:11:24AM +0800, çè 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

>