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Date: Fri, 10 Dec 2004 16:26:23 -0800
From: Andrew Morton <akpm@osdl.org>
To: Konstantin Kletschke <lists@ku-gbr.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: How do klogd and syslogd influence code execution timing?
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Konstantin Kletschke <lists@ku-gbr.de> wrote:
>
> It is absolutely _required_ that we start syslogd and klogd before
> inserting the storage device.

The difference is that if klogd is running, a printk() will cause a wakeup
to be delivered to klogd in release_console_sem().  That will cause the CPU
to go into the scheduler code, take and release locks, take more time, etc.