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Date:   Wed, 7 Sep 2022 19:34:40 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Oleksandr Natalenko <oleksandr@redhat.com>
Cc:     "Eric W. Biederman" <ebiederm@xmission.com>,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Huang Ying <ying.huang@intel.com>,
        "Jason A . Donenfeld" <Jason@zx2c4.com>,
        Will Deacon <will@kernel.org>,
        "Guilherme G . Piccoli" <gpiccoli@igalia.com>,
        Laurent Dufour <ldufour@linux.ibm.com>,
        Stephen Kitt <steve@sk2.org>, Rob Herring <robh@kernel.org>,
        Joel Savitz <jsavitz@redhat.com>,
        Kees Cook <keescook@chromium.org>,
        Xiaoming Ni <nixiaoming@huawei.com>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Renaud =?iso-8859-1?Q?M=E9trich?= <rmetrich@redhat.com>,
        Grzegorz Halat <ghalat@redhat.com>, Qi Guo <qguo@redhat.com>
Subject: Re: [PATCH] core_pattern: add CPU specifier
Message-ID: <20220907173438.GA15992@redhat.com>
References: <20220903064330.20772-1-oleksandr@redhat.com>
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On 09/07, Oleksandr Natalenko wrote:
>
> The advantage of having CPU recorded in the file name is that
> in case of multiple cores one can summarise them with a simple
> ls+grep without invoking a fully-featured debugger to find out
> whether the segfaults happened on the same CPU.

Besides, if you only need to gather the statistics about the faulting
CPU(s), you do not even need to actually dump the the core. For example,
something like

	#!/usr/bin/sh

	echo $* >> path/to/coredump-stat.txt

and
	echo '| path-to-script-above %C' >/proc/sys/kernel/core_pattern

can help.

Oleg.