Subject: Re: pstore/ramoops - why only collect a partial dmesg?
To:     "Luck, Tony" <tony.luck@intel.com>,
        "keescook@chromium.org" <keescook@chromium.org>,
        "anton@enomsg.org" <anton@enomsg.org>,
        "ccross@android.com" <ccross@android.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Linux-Fsdevel <linux-fsdevel@vger.kernel.org>,
        "Guilherme G. Piccoli" <kernel@gpiccoli.net>
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From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Message-ID: <b2d66d9f-15a6-415c-2485-44649027a1d5@igalia.com>
Date:   Tue, 4 Jan 2022 16:36:43 -0300
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On 04/01/2022 15:46, Luck, Tony wrote:
> That does change things ... I wonder how many megabytes you need
> for a big system (hundreds of cores, thousands of tasks)!

Heheh indeed, this case would require a very big log buffer I guess! But
our setup is not so big, only 4/8 CPUs, not so much RAM and not that
many tasks expected, opposed to a big server with maybe multiple VMs,
containers, etc...

> 
> This use case does look like it could use multiple chunks in ramoops.

Cool, thanks! If nobody complains or show any reason in that ramoops
shouldn't be changed to deal with multi-chunk dmesg, I'll try to come up
with something then.

Cheers,


Guilherme