From: Wei Yang <richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org>
Cc: Wei Yang
<richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
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Subject: Re: [PATCH 4/4] mm/memcg: refine mem_cgroup_threshold_ary->current_threshold calculation
Date: Wed, 12 Jan 2022 00:25:51 +0000 [thread overview]
Message-ID: <20220112002551.sksmoril2nwuddtu@master> (raw)
In-Reply-To: <Yd3LLalWzPy17PmR-cx5fftMpWqeCjSd+JxjunQ2O0Ztt9esIQQ4Iyu8u01E@public.gmane.org>
On Tue, Jan 11, 2022 at 10:23:41AM -0800, Roman Gushchin wrote:
>On Tue, Jan 11, 2022 at 01:03:02AM +0000, Wei Yang wrote:
>> mem_cgroup_threshold_ary->current_threshold points to the last entry
>> who's threshold is less or equal to usage.
>>
>> Instead of iterating entries to get the correct index, we can leverage
>> primary->current_threshold to get it. If the threshold added is less or
>> equal to usage, current_threshold should increase by one. Otherwise, it
>> doesn't change.
>
>How big is usually an array of thresholds? If it's not huge, likely
>any savings won't be really noticeable (it's not a hot path and there
>is an rc_synchronize() below).
Usually the size is small I think.
>
>So I agree with Michal that a better justification is really needed.
Yep.
>
>Thanks!
--
Wei Yang
Help you, Help me
next prev parent reply other threads:[~2022-01-12 0:25 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-11 1:02 [PATCH 1/4] mm/memcg: use NUMA_NO_NODE to indicate allocation from unspecified node Wei Yang
2022-01-11 1:03 ` [PATCH 2/4] mm/memcg: mem_cgroup_per_node is already set to 0 on allocation Wei Yang
[not found] ` <20220111010302.8864-2-richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2022-01-11 2:25 ` Muchun Song
2022-01-11 18:06 ` Roman Gushchin
2022-01-16 19:24 ` Shakeel Butt
2022-01-11 8:41 ` Michal Hocko
2022-01-14 11:08 ` Mike Rapoport
[not found] ` <20220111010302.8864-1-richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2022-01-11 1:03 ` [PATCH 3/4] mm/memcg: retrieve parent memcg from css.parent Wei Yang
[not found] ` <20220111010302.8864-3-richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2022-01-11 3:12 ` Muchun Song
2022-01-11 18:09 ` Roman Gushchin
[not found] ` <Yd3H8Hea6dBlkzeW-cx5fftMpWqeCjSd+JxjunQ2O0Ztt9esIQQ4Iyu8u01E@public.gmane.org>
2022-01-12 0:24 ` Wei Yang
2022-01-16 19:54 ` Shakeel Butt
2022-01-11 8:43 ` Michal Hocko
2022-01-11 1:03 ` [PATCH 4/4] mm/memcg: refine mem_cgroup_threshold_ary->current_threshold calculation Wei Yang
2022-01-11 8:44 ` Michal Hocko
[not found] ` <20220111010302.8864-4-richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2022-01-11 18:23 ` Roman Gushchin
[not found] ` <Yd3LLalWzPy17PmR-cx5fftMpWqeCjSd+JxjunQ2O0Ztt9esIQQ4Iyu8u01E@public.gmane.org>
2022-01-12 0:25 ` Wei Yang [this message]
2022-01-11 2:23 ` [PATCH 1/4] mm/memcg: use NUMA_NO_NODE to indicate allocation from unspecified node Muchun Song
2022-01-11 8:40 ` Michal Hocko
[not found] ` <Yd1CdJA5NelzoK1D-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org>
2022-01-12 0:46 ` Wei Yang
2022-01-12 8:56 ` Michal Hocko
[not found] ` <Yd6Xr7K9bKGVgGtI-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org>
2022-01-14 0:29 ` Wei Yang
2022-01-14 8:51 ` Michal Hocko
[not found] ` <YeE5k79uP3xBPCv7-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org>
2022-01-15 22:10 ` Wei Yang
2022-01-16 19:23 ` Shakeel Butt
2022-01-11 18:05 ` Roman Gushchin
2022-01-14 11:07 ` Mike Rapoport
2022-01-31 1:47 ` Wei Yang
2022-01-31 22:36 ` Andrew Morton
[not found] ` <20220131143620.b619f24f5246b26bce2b717d-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
2022-02-01 0:42 ` Wei Yang
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