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Date: Wed, 22 Dec 2010 22:21:12 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Mike Travis <travis@sgi.com>
Cc: Tejun Heo <tj@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Rientjes <rientjes@google.com>, Len Brown <lenb@kernel.org>,
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        "linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: Early kernel messages are overflowing the static log buffer
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* Mike Travis <travis@sgi.com> wrote:

> Thanks.
> 
> I have a patchset almost ready for submission.  We have a giant
> system (6 racks with some huge amount of nodes) for a few more
> days, and the buffer still overflowed with my changes.  So I'm
> making one more tweak to cut down the amount of characters generated
> without losing information.

Also feel free to make judgement calls to cut information - people _think_ they need 
all that boot time noise but it's rarely useful. Memory layout is - but a lot of 
other details are not. So dont try to preserve things at any cost.

> This doesn't really help the log buffer overflow problem as KERN_DEBUG
> messages still end up in the buffer.  The pr_debug() macro does compile
> out the messages if the system does not have KERNEL debug set, though
> distros also have this set as a default.

Make the whole printout dependent on a percpu-debug boot parameter? (and default the 
switch to off?)

Thanks,

	Ingo