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From:   Ilya Dryomov <idryomov@gmail.com>
Date:   Mon, 25 Sep 2023 12:41:51 +0200
Message-ID: <CAOi1vP80WvQhuXgzhvzupQP=4K2ckgu_WpUCtUSy5M+QdDycqw@mail.gmail.com>
Subject: Re: [PATCH 1/2] fs/ceph/debugfs: make all files world-readable
To:     Max Kellermann <max.kellermann@ionos.com>
Cc:     Xiubo Li <xiubli@redhat.com>, Jeff Layton <jlayton@kernel.org>,
        ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org
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On Fri, Sep 22, 2023 at 8:26=E2=80=AFAM Max Kellermann <max.kellermann@iono=
s.com> wrote:
>
> I'd like to be able to run metrics collector processes without special
> privileges

Hi Max,

A word of caution about building metrics collectors based on debugfs
output: there are no stability guarantees.  While the format won't be
changed just for the sake of change of course, expect zero effort to
preserve backwards compatibility.

The latency metrics in particular are sent to the MDS in binary form
and are intended to be consumed through commands like "ceph fs top".
debugfs stuff is there just for an occasional sneak peek (apart from
actual debugging).

Thanks,

                Ilya