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Subject: Re: [RFC/Requirements/Design] h/w error reporting
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Steven Rostedt <rostedt@goodmis.org>
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On Wed, 2010-11-10 at 13:05 -0500, Steven Rostedt wrote:
> 
> Peter said at LPC that the perf buffering system was not designed to
> handle high speed tracing. But he also said he does not like the way the
> ftrace buffering works. 

You're not very good at listening, I said the perf infrastructure and
event handling mechanism isn't geared towards full throughput but
instead on sampling.

There is lots of code between getting the event and landing it in the
buffer. The buffer itself is perfectly suited for high speed low
overhead stuffs, the perf data format possibly not because its not
bitfield happy.