Re: [PATCH] mm/khugepaged: sched to numa node when collapse huge page

From: maobibo
Date: Fri Mar 11 2022 - 05:13:03 EST




On 03/11/2022 05:55 PM, David Hildenbrand wrote:
> On 11.03.22 10:51, maobibo wrote:
>>
>>
>> On 03/11/2022 05:20 PM, David Hildenbrand wrote:
>>> On 11.03.22 10:01, Bibo Mao wrote:
>>>> collapse huge page is slow, specially when khugepaged daemon runs
>>>> on different numa node with that of huge page. It suffers from
>>>> huge page copying across nodes, also cache is not used for target
>>>> node. With this patch, khugepaged daemon switches to the same numa
>>>> node with huge page. It saves copying time and makes use of local
>>>> cache better.
>>>
>>> Hi,
>>>
>>> just the usual question, do you have any performance numbers to back
>>> your claims (e.g., "is slow, specially when") and proof that this patch
>>> does the trick?
>> With specint 2006 on loongarch 3C5000L 32core numa system, it improves
>> about 6%. The page size is 16K and pmd page size is 32M, memory performance
>> across numa node is obvious different. However I do not test it on x86 box.
>>
>
> Thanks, can you add these details to the patch description?
Surely, will do in next patch.

regards
bibo, mao
>
>