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Date: Tue, 23 Sep 2008 11:28:17 -0700
From: "Martin Bligh" <mbligh@google.com>
To: "KOSAKI Motohiro" <kosaki.motohiro@jp.fujitsu.com>
Subject: Re: Unified tracing buffer
Cc: "Masami Hiramatsu" <mhiramat@redhat.com>,
       "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
       "Linus Torvalds" <torvalds@linux-foundation.org>,
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       "Frank Ch. Eigler" <fche@redhat.com>,
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>> I think the main reason of using single-channel mode is simplicity of
>> userspace reader. We can use 'cat' or 'tail' to read the buffer on-line.
>> I'm not sure how much overhead ftrace-like buffer merging routine has,
>> but if kernel provides an interface which gives us single-merged buffer
>> image(like ftrace buffer), we are grad to use it. :-)
>
> Yup, I also think it is better.

That was the plan, yes. Merge sort is cheap ;-)