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Date:   Thu, 8 Apr 2021 09:51:17 +0200
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Daniel Xu <dxu@dxuuu.xyz>
Cc:     bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        kernel-team@fb.com, jolsa@kernel.org, hannes@cmpxchg.org,
        yhs@fb.com
Subject: Re: [RFC bpf-next 0/1] bpf: Add page cache iterator
Message-ID: <20210408075117.oqoqspilk3c3xsaa@wittgenstein>
References: <cover.1617831474.git.dxu@dxuuu.xyz>
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On Wed, Apr 07, 2021 at 02:46:10PM -0700, Daniel Xu wrote:
> There currently does not exist a way to answer the question: "What is in
> the page cache?". There are various heuristics and counters but nothing
> that can tell you anything like:
> 
>   * 3M from /home/dxu/foo.txt
>   * 5K from ...
>   * etc.
> 
> The answer to the question is particularly useful in the stacked
> container world. Stacked containers implies multiple containers are run
> on the same physical host. Memory is precious resource on some (if not

Just to clarify: what are "stacked containers"? Do you mean nested
containers, i.e. containers running within containers?

Christian