Re: [mm/hugetlb] c77c0a8ac4: will-it-scale.per_process_ops 15.9% improvement

[Waiman Long]

On 1/14/20 4:12 AM, Michal Hocko wrote:
> On Tue 14-01-20 16:56:37, kernel test robot wrote:
>> Greeting,
>>
>> FYI, we noticed a 15.9% improvement of will-it-scale.per_process_ops due to commit:
>>
>>
>> commit: c77c0a8ac4c522638a8242fcb9de9496e3cdbb2d ("mm/hugetlb: defer freeing of huge pages if in non-task context")
>> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> This is more than surprising because the patch has only changed the
> behavior for hugetlb pages freed from the (soft)interrupt context and
> that should be a very rare event. Does the test really generate a lot of
> those?
>
Yes, I have the same question. I was not expecting to see any
performance impact.

Cheers,
Longman