Re: [PATCH 2/2] sched: add statistic for rq->max_idle_balance_cost

[Alex Shi]

On 01/23/2014 05:54 PM, Peter Zijlstra wrote:
> On Thu, Jan 23, 2014 at 02:49:25PM +0800, Alex Shi wrote:
>> On 01/23/2014 02:10 AM, Jason Low wrote:
>>>>>>>  	P64(avg_idle);
>>>>>>> +	P64(max_idle_balance_cost);
>>>>>>>  #endif
>>>>>>>   	P(ttwu_count);
>>>>>
>>>>> Not also the per-sd value in sd_alloc_ctl_domain_table() ?
>>> Yeah, tracking the sd->max_newidle_lb_cost can also be useful.
>>>
>>>
>>
>> Thanks for suggestion!
>>
>> I thought the sd->max_newidle_lb_cost keep changing. But yes, it's
>> still meaningful. 
>> BTW, in the pandaboard ES, sd balance cost is about 1~2ms.
> 
> That's an insane amount of time for only 2 cpus.

maybe, :(

but it is the data.
$ cat /proc/sys/kernel/sched_domain/cpu0/domain0/max_newidle_lb_cost
1873393

> 
>> ---
>>

[...]
>>  sd_alloc_ctl_domain_table(struct sched_domain *sd)
>>  {
>> -	struct ctl_table *table = sd_alloc_ctl_entry(8);
>> +	struct ctl_table *table = sd_alloc_ctl_entry(9);
> 
> tip/master has 13 there, not 8.
> 

Sorry about this. updated on tip/master.

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