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Subject: Re: Perf and ftrace [was Re: PyTimechart]
From: Peter Zijlstra <peterz@infradead.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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On Wed, 2010-05-12 at 14:51 -0400, Mathieu Desnoyers wrote:
> 
> It makes it hard to use splice() or read() if you don't specify the buffer size
> at creation time. That alone seems like a pretty good argument for fixing the
> size before the mmap() call. 

Our read() doesn't actually provide the same data splice()/mmap() would.
But yeah, hence my proposal to create a separate syscall that creates
buffer objects.