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Date: Tue, 19 Dec 2017 07:24:44 -0800
From: Tejun Heo <tj@kernel.org>
To: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@kernel.org>, Li Zefan <lizefan@huawei.com>,
        Roman Gushchin <guro@fb.com>,
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Subject: Re: [RFC PATCH] mm: memcontrol: memory+swap accounting for cgroup-v2
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Hello,

On Tue, Dec 19, 2017 at 07:12:19AM -0800, Shakeel Butt wrote:
> Yes, there are pros & cons, therefore we should give users the option
> to select the API that is better suited for their use-cases and

Heh, that's not how API decisions should be made.  The long term
outcome would be really really bad.

> environment. Both approaches are not interchangeable. We use memsw
> internally for use-cases I mentioned in commit message. This is one of
> the main blockers for us to even consider cgroup-v2 for memory
> controller.

Let's concentrate on the use case.  I couldn't quite understand what
was missing from your description.  You said that it'd make things
easier for the centralized monitoring system which isn't really a
description of a use case.  Can you please go into more details
focusing on the eventual goals (rather than what's currently
implemented)?

Thanks.

-- 
tejun