[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <8c1fc6d4-7d3a-85dd-ebd9-fc8e221f1878@loongson.cn>
Date: Fri, 13 May 2022 09:19:08 +0800
From: maobibo <maobibo@...ngson.cn>
To: Andrew Morton <akpm@...ux-foundation.org>,
Peter Xu <peterx@...hat.com>
Cc: David Hildenbrand <david@...hat.com>, linux-mm@...ck.org,
linux-kernel@...r.kernel.org, Yang Shi <shy828301@...il.com>
Subject: Re: [PATCH v3] mm/khugepaged: sched to numa node when collapse huge
page
在 2022/5/13 08:36, Andrew Morton 写道:
> On Thu, 28 Apr 2022 12:34:07 -0400 Peter Xu <peterx@...hat.com> wrote:
>
>> On Thu, Apr 28, 2022 at 05:17:07PM +0200, David Hildenbrand wrote:
>>> On 17.03.22 07:50, Bibo Mao wrote:
>>>> collapse huge page will copy huge page from general small pages,
>>>> dest node is calculated from most one of source pages, however
>>>> THP daemon is not scheduled on dest node. The performance may be
>>>> poor since 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.
>>>>
>>>> With this patch, specint 2006 base performance is improved with 6%
>>>> on Loongson 3C5000L platform with 32 cores and 8 numa nodes.
>>>
>>> If it helps, that's nice as long as it doesn't hurt other cases.
>>>
>
> Quite a bit of doubtful feedback and we have yet to hear from the
> author. I'll drop the patch.
>
> Bibo, please resend at a later time if you feel the patch remains
> desirable. Please attempt to address the feedback via code changes
> and/or changelogging.
Sorry for the late response, the mail is filtered and I did not notice that. The result is not so obvious after bandwidth is improved between nodes, it is only about 1% improvement for specint2006 for 32 core on my box.
Now I do not see negative effective about this patch unless user wants to keep some cores separated from khugepaged daemon process.
regards
bibo,mao
Powered by blists - more mailing lists