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From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Jeroen Van den Keybus <jeroen.vandenkeybus@gmail.com>
Cc: "xenomai@xenomai.org" <xenomai@xenomai.org>
Subject: Re: [Xenomai] Slow execution of RT task
Date: Mon, 14 Apr 2014 22:33:12 +0200	[thread overview]
Message-ID: <534C4608.9090200@xenomai.org> (raw)
In-Reply-To: <CAPRPZsCkGj=n4LJeduM5MJM0UbAcjwg+5uZkNnAn9dSGwaKeoQ@mail.gmail.com>

On 04/14/2014 10:18 PM, Jeroen Van den Keybus wrote:
>> Do you have CONFIG_NO_HZ_FULL enabled? If so, could you disable it and
>> retry? Next step, same question for CONFIG_NO_HZ_IDLE.
> 
> Same results, but now latency figures are somewhat higher:
> 
> RTT|  00:00:01  (periodic user-mode task, 100 us period, priority 99)
> RTH|----lat min|----lat avg|----lat max|-overrun|---msw|---lat best|--lat worst
> RTD|      0.035|      0.288|      7.512|       0|     0|      0.035|      7.512
> RTD|     -0.661|      0.294|      7.626|       0|     0|     -0.661|      7.626
> RTD|     -0.680|      0.293|      7.907|       0|     0|     -0.680|      7.907
> 
> rt_timer_read still requires 1.6 us (or at least that's what I get
> back from rt_timer_read).

Maybe the clocksource is no longer the tsc? What does:

cat /sys/devices/system/clocksource/clocksource0/current_clocksource

say?


-- 
                                                                Gilles.


  reply	other threads:[~2014-04-14 20:33 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-14  9:14 [Xenomai] Slow execution of RT task Jeroen Van den Keybus
2014-04-14 12:28 ` Philippe Gerum
2014-04-14 12:45   ` Jeroen Van den Keybus
2014-04-14 12:53     ` Philippe Gerum
2014-04-15 14:40     ` Philippe Gerum
2014-04-16  9:43       ` Jeroen Van den Keybus
2014-04-16 14:23         ` Philippe Gerum
2014-04-16 20:42           ` Jeroen Van den Keybus
2014-04-24 10:21             ` Jeroen Van den Keybus
2014-04-24 12:17               ` Philippe Gerum
2014-04-14 12:44 ` Philippe Gerum
2014-04-14 12:47   ` Jeroen Van den Keybus
2014-04-14 20:18   ` Jeroen Van den Keybus
2014-04-14 20:33     ` Gilles Chanteperdrix [this message]
2014-04-14 21:14       ` Jeroen Van den Keybus

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