Re: [PATCH 3/3] mm/memcg: add next_mz back if not reclaimed yet

Wei Yang
2022-03-10T01:13:54Z

On Wed, Mar 09, 2022 at 02:48:45PM +0100, Michal Hocko wrote:
>[Cc Tim - the patch is http://lkml.kernel.org/r/20220308012047.26638-3-richard.weiyang@gmail.com]
>
>On Wed 09-03-22 00:46:20, Wei Yang wrote:
>> On Tue, Mar 08, 2022 at 09:17:58AM +0100, Michal Hocko wrote:
>> >On Tue 08-03-22 01:20:47, Wei Yang wrote:
>> >> next_mz is removed from rb_tree, let's add it back if no reclaim has
>> >> been tried.
>> >
>> >Could you elaborate more why we need/want this?
>> >
>>
>> Per my understanding, we add back the right most node even reclaim makes no
>> progress, so it is reasonable to add back a node if we didn't get a chance to
>> do reclaim on it.
>
>Your patch sounded familiar and I can remember now. The same fix has
>been posted by Tim last year
>https://lore.kernel.org/linux-mm/8d35206601ccf0e1fe021d24405b2a0c2f4e052f.1613584277.git.tim.c.chen@linux.intel.com/
>It was posted with other changes to the soft limit code which I didn't
>like but I have acked this particular one. Not sure what has happened
>with it afterwards.

Because of this ?
4f09feb8bf: vm-scalability.throughput -4.3% regression
https://lore.kernel.org/linux-mm/20210302062521.GB23892@xsang-OptiPlex-9020/

>--
>Michal Hocko
>SUSE Labs

--
Wei Yang
Help you, Help me