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Date: Tue, 19 Dec 2017 13:41:07 -0800
From: Tejun Heo <tj@kernel.org>
To: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@kernel.org>, Li Zefan <lizefan@huawei.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 10:25:12AM -0800, Shakeel Butt wrote:
> Making the runtime environment, an invariant is very critical to make
> the management of a job easier whose instances run on different
> clusters across the world. Some clusters might have different type of
> swaps installed while some might not have one at all and the
> availability of the swap can be dynamic (i.e. swap medium outage).
> 
> So, if users want to run multiple instances of a job across multiple
> clusters, they should be able to specify the limits of their jobs
> irrespective of the knowledge of cluster. The best case would be they
> just submits their jobs without any config and the system figures out
> the right limit and enforce that. And to figure out the right limit
> and enforcing it, the consistent memory usage history and consistent
> memory limit enforcement is very critical.

I'm having a hard time extracting anything concrete from your
explanation on why memsw is required.  Can you please ELI5 with some
examples?

Thanks.

-- 
tejun