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From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Thierry Bultel <thierry.bultel@wanadoo.fr>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai] iMX6q 1Hz tick
Date: Tue, 11 Dec 2012 18:40:51 +0100	[thread overview]
Message-ID: <50C77023.5080000@xenomai.org> (raw)
In-Reply-To: <50C76DAC.6020603@wanadoo.fr>

On 12/11/2012 06:30 PM, Thierry Bultel wrote:
> Le 11/12/2012 17:50, Gilles Chanteperdrix a écrit :
>> On 12/11/2012 05:01 PM, Thierry Bultel wrote:
>>> Le 11/12/2012 16:36, Gilles Chanteperdrix a écrit :
>>>> On 12/11/2012 04:26 PM, Thierry Bultel wrote:
>>>>> Gilles,
>>>>>
>>>>> another issue (likely related, and that may help to diagnose) that I can
>>>>> see is that time is completely wrong;
>>>>>
>>>>> For instance:
>>>>>
>>>>>
>>>>> [root@buildroot ~]# time sleep 10
>>>>>
>>>>> real	0m10.009s
>>>>> user	0m0.002s
>>>>> sys	0m0.013s
>>>>>
>>>>> The system says that it spent 10 secs but I actually measured 25 secs.
>>>>
>>>> No, that is likely because you have CONFIG_CPU_FREQ or CONFIG_CPU_IDLE
>>>> enabled.
>>>>
>>>
>>> Thanks, yes this was CONFIG_CPU_FREQ
>>
>> Ok, and when running at full speed, do the timer thread always take 20%
>> cpu ?
>>
> 
> It is much better. I only have 1.3% of CPU load.
> Also the target seems really stable now. Thanks a lot, again.
> 
> The only remaining 'weird' issue is that the iMX Timer Tick counter in 
> /proc/interrupts does not increase whereas it does when CONFIG_IPIPE is 
> set to NO. It is not really a blocking issue, but I would like to 
> understand why.

Could you check if you have the issue with the I-pipe kernel for Linux
3.4.6, available in xenomai git?

git://git.denx.de/ipipe.git branch core-3.4

-- 
					    Gilles.


      reply	other threads:[~2012-12-11 17:40 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-07 13:28 [Xenomai] iMX6q 1Hz tick Thierry Bultel
2012-12-07 18:34 ` Gilles Chanteperdrix
2012-12-09 20:06   ` Thierry Bultel
2012-12-09 23:54     ` Gilles Chanteperdrix
2012-12-10 14:53       ` Thierry Bultel
2012-12-10 16:01         ` Gilles Chanteperdrix
2012-12-10 16:31           ` Thierry Bultel
2012-12-10 17:37             ` Gilles Chanteperdrix
2012-12-10 18:34               ` Thierry Bultel
2012-12-10 18:56                 ` Gilles Chanteperdrix
2012-12-10 20:02                   ` Thierry Bultel
2012-12-10 20:19                     ` Gilles Chanteperdrix
2012-12-10 21:09                       ` Thierry Bultel
2012-12-10 21:22                         ` Gilles Chanteperdrix
2012-12-11 15:26                           ` Thierry Bultel
2012-12-11 15:36                             ` Gilles Chanteperdrix
2012-12-11 16:01                               ` Thierry Bultel
2012-12-11 16:50                                 ` Gilles Chanteperdrix
2012-12-11 17:30                                   ` Thierry Bultel
2012-12-11 17:40                                     ` Gilles Chanteperdrix [this message]

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