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Date: Fri, 26 Sep 2008 06:47:27 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
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To: Peter Zijlstra <peterz@infradead.org>
cc: Mathieu Desnoyers <compudj@krystal.dyndns.org>,
       Masami Hiramatsu <mhiramat@redhat.com>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>,
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       hch@lst.de, Martin Bligh <mbligh@google.com>,
       Christoph Hellwig <hch@infradead.org>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [RFC PATCH v4] Unified trace buffer
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On Fri, 26 Sep 2008, Peter Zijlstra wrote:
> > 
> > You could also fallback on a 2-level page array when buffer size is >
> > 64MB. The cost is mainly a supplementary pointer dereference, but one
> > more should not make sure a big difference overall.
> 
> I'm still not sure why we don't just link the pages using the page
> frames, we don't need the random access, do we?


Hmm, but this does make changing the buffer size much easier. I'll think 
about it  and perhaps try it out. If I can tidy it up nicer than the 
ftrace code, then I may include it for v1.

-- Steve