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Date: Thu, 7 Nov 2013 17:59:37 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jan Kara <jack@suse.cz>, Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>, Michal Hocko <mhocko@suse.cz>
Subject: Re: [PATCH 3/4] printk: Defer printing to irq work when we printed
 too much
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On Thu, 7 Nov 2013 23:43:52 +0100
Frederic Weisbecker <fweisbec@gmail.com> wrote:


> When a message takes tens of seconds to be printed, it usually means
> we are in trouble somehow :)
> I wonder what printk source can trigger such a high volume.

The only ones that I'm aware of is the prints from sysrq. Which
includes a ftrace_dump as well. These have caused issues in the past,
but usually I do them on boxes that I reboot afterward anyway.

-- Steve