From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <52D531E4.4040407@xenomai.org> Date: Tue, 14 Jan 2014 13:47:32 +0100 From: Gilles Chanteperdrix MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai] filter ipipe tracing List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Cc: xenomai@xenomai.org On 01/14/2014 01:35 PM, David wrote: > Dear, > > I'm actually tracing my Xenomai drivers/syscalls thanks to the ipipe trace > facility. Actually, every "ipipe/xenomai/rtdm drivers" procedures are > traced. I give a try with 5000 points, I'm able to trace about 5ms of > execution. This is already a huge help for some problems but (a) it is too > short for my new needs. The performance impact of tracing appears big > (about x2 on performance ?), (b) it makes my application instable (100% of > CPU usage). > > (a) Is it possible to trace about 1-10s of execution ? (any hint ?). > (b) Could we reduce performance impact for tracing ? I used FTRACE in the > past, it was possible to filter the events or procedure names traced but I > don't know how to proceed with ipipe tracing. If you are only interested in the events you generate, then you can disable tracing of function entries and exit, and generate the events you are interested in with ipipe_trace_special. -- Gilles.