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References: <20240427003733.3898961-1-shakeel.butt@linux.dev> <20240427003733.3898961-4-shakeel.butt@linux.dev>
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From: Yosry Ahmed <yosryahmed@google.com>
Date: Fri, 26 Apr 2024 17:51:23 -0700
Message-ID: <CAJD7tkY2EwtOHh3w=e0+OC3gOPb9xCC7C36BhM0RHYPv184U+Q@mail.gmail.com>
Subject: Re: [PATCH v2 3/7] memcg: reduce memory for the lruvec and memcg stats
To: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Andrew Morton <akpm@linux-foundation.org>, Johannes Weiner <hannes@cmpxchg.org>, 
	Michal Hocko <mhocko@kernel.org>, Roman Gushchin <roman.gushchin@linux.dev>, 
	Muchun Song <muchun.song@linux.dev>, linux-mm@kvack.org, linux-kernel@vger.kernel.org
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On Fri, Apr 26, 2024 at 5:37=E2=80=AFPM Shakeel Butt <shakeel.butt@linux.de=
v> wrote:
>
> At the moment, the amount of memory allocated for stats related structs
> in the mem_cgroup corresponds to the size of enum node_stat_item.
> However not all fields in enum node_stat_item has corresponding memcg
> stats. So, let's use indirection mechanism similar to the one used for
> memcg vmstats management.

Just curious, does the indirection table cause any noticeable
performance impact? My guess is no, but the update paths are usually
very performance sensitive.

I guess lkp will shout at us if there are any noticeable regressions.