Re: [PATCH v2 2/3] sched/fair: Move hot load_avg into its own cacheline

Waiman Long
2015-12-03T19:34:51Z

On 12/02/2015 11:32 PM, Mike Galbraith wrote:
> On Wed, 2015-12-02 at 13:41 -0500, Waiman Long wrote:
>
>> By doing so, the perf profile became:
>>
>> 9.44% 0.00% java [kernel.vmlinux] [k] smp_apic_timer_interrupt
>> 8.74% 0.01% java [kernel.vmlinux] [k] hrtimer_interrupt
>> 7.83% 0.03% java [kernel.vmlinux] [k] tick_sched_timer
>> 7.74% 0.00% java [kernel.vmlinux] [k] update_process_times
>> 7.27% 0.03% java [kernel.vmlinux] [k] scheduler_tick
>> 5.94% 1.74% java [kernel.vmlinux] [k] task_tick_fair
>> 4.15% 3.92% java [kernel.vmlinux] [k] update_cfs_shares
>>
>> The %cpu time is still pretty high, but it is better than before.
> Is that with the box booted skew_tick=1?
>
> -Mike
>

I haven't tried that kernel parameter. I will try it to see if it can
improve the situation. BTW, will there be other undesirable side effects
of using this other than the increased power consumption as said in the
kernel-parameters.txt file?

Cheers,
Longman