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Message-ID: <fa628406-23db-47be-b9c1-ef8a88ecd062@linux.dev>
Date: Fri, 19 Jan 2024 23:05:11 +0800
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Subject: Re: [PATCH v4 3/7] padata: dispatch works on different nodes
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To: Tim Chen <tim.c.chen@linux.intel.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
 David Hildenbrand <david@redhat.com>, David Rientjes <rientjes@google.com>,
 Mike Kravetz <mike.kravetz@oracle.com>, Muchun Song <muchun.song@linux.dev>,
 Andrew Morton <akpm@linux-foundation.org>, ligang.bdlg@bytedance.com
References: <20240118123911.88833-1-gang.li@linux.dev>
 <20240118123911.88833-4-gang.li@linux.dev>
 <29695e89ae2d838c9b7537941b0231c3ff559e48.camel@linux.intel.com>
From: Gang Li <gang.li@linux.dev>
In-Reply-To: <29695e89ae2d838c9b7537941b0231c3ff559e48.camel@linux.intel.com>
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On 2024/1/19 07:04, Tim Chen wrote:
> On Thu, 2024-01-18 at 20:39 +0800, Gang Li wrote:
>> When a group of tasks that access different nodes are scheduled on the
>> same node, they may encounter bandwidth bottlenecks and access latency.
>>
>> Thus, numa_aware flag is introduced here, allowing tasks to be
>> distributed across different nodes to fully utilize the advantage of
>> multi-node systems.
>>
>> Signed-off-by: Gang Li <gang.li@linux.dev>
>> Tested-by: David Rientjes <rientjes@google.com>
>> ---
>>   include/linux/padata.h |  3 +++
>>   kernel/padata.c        | 14 ++++++++++++--
>>   mm/mm_init.c           |  1 +
>>   3 files changed, 16 insertions(+), 2 deletions(-)
>>
>> diff --git a/include/linux/padata.h b/include/linux/padata.h
>> index 495b16b6b4d7..f79ccd50e7f4 100644
>> --- a/include/linux/padata.h
>> +++ b/include/linux/padata.h
>> @@ -137,6 +137,8 @@ struct padata_shell {
>>    *             appropriate for one worker thread to do at once.
>>    * @max_threads: Max threads to use for the job, actual number may be less
>>    *               depending on task size and minimum chunk size.
>> + * @numa_aware: Dispatch jobs to different nodes. If a node only has memory but
>> + *              no CPU, dispatch its jobs to a random CPU.
> 
> Suggest:
> Distribute jobs to different nodes with CPU in a round robin fashion.
> 

Good idea.
Thanks.

>>    */
>>   struct padata_mt_job {
>