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Date: Thu, 24 Apr 2014 00:25:59 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai] Reading /proc/xenomai/stat causes high latencies
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To: Jeroen Van den Keybus <jeroen.vandenkeybus@gmail.com>
Cc: "xenomai@xenomai.org" <xenomai@xenomai.org>

On 04/23/2014 11:39 PM, Jeroen Van den Keybus wrote:
>> You mean with tracer on? Then you have a trace for the high latency?
> 
> No, unfortunately. Every time I enable the tracer, all is well, no latencies.
> 
> Since this is so elusive, I started to install all kernels I built
> (and keep the configs along). I just found that one of them does not
> have the high latencies and does not have the I-pipe debugging on
> either. Hooray.
> 
> However, when I powerdown the machine and reboot this very kernel, the
> problem reappears.

Could you put a printk in the function vfile_stat_rewind to see if it
gets called (more than once) when the problem happens?


-- 
                                                                Gilles.