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Subject: Re: Perf and ftrace [was Re: PyTimechart]
From: Steven Rostedt <rostedt@goodmis.org>
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To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
       Frederic Weisbecker <fweisbec@gmail.com>,
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On Wed, 2010-05-12 at 14:37 -0400, Mathieu Desnoyers wrote:

> OK, I see. In LTTng, I dropped the mmap() support when I integrated splice(). In
> both case, I can share the pages between the "output" (mmap or splice) and the
> ring buffer because my ring buffer does not care about
> page->mapping/->index/etc, so I never have to swap them.

I'm curious, how do you handle the overwrite mode without swapping?

-- Steve