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Date: Wed, 25 Feb 2009 11:00:53 +0200
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Subject: Re: [PATCH 2/4] tracing: add event trace infrastructure
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
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Hi Andrew,

On Wed, Feb 25, 2009 at 10:28 AM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> A better approach would be to design simple, robust kernel interfaces
> which make sense and which aren't made all complex by putting the user
> interface in kernel space.  And to maintain corresponding userspace
> tools which manipulate and present the IO from those kernel interfaces.

We did this for kmemtrace and quite frankly, I usually end up spending
more time figuring out how to export the data from a virtual machine
than actually analyzing the results. What makes ftrace so cool is the
fact that it has almost zero-overhead for setup and that the
text-based data format plays well with simple scripting tools
available everywhere.

                                     Pekka