[Xenomai] The cyclictest test shows high latencies

[Xenomai] The cyclictest test shows high latencies

[zhengguang.yang(杨争光)]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset="gb2312", Size: 1065 bytes --]

Dear Xenomai Team:
I want to use xenomai on imx6q.
When I install it according to your wiki, then check the kernel boot log:

# dmesg |grep -i xenomai
[    0.408274] [Xenomai] scheduling class idle registered.
[    0.408281] [Xenomai] scheduling class rt registered.
[    0.408538] I-pipe: head domain Xenomai registered.
[    0.412129] [Xenomai] Cobalt v3.0.7 (Lingering Dawn)

However, after testing with cyclictest, it seems that there is no difference between xenomai-linux and non_xenomai-linux.


¡¤         Maybe I did something wrong and what goes wrong that leads to this result?

Best Regards

Zhengguang.yang /ÑîÕù¹â
ÑÐÈA¿Æ¼¼(ÖЇø)ÓÐÏÞ¹«Ë¾
E-mail: zhengguang.yang@advantech.com.cn<mailto:racer.jui@advantech.com.cn>
Tel: 0512-57775666 Ext:9813
[cid:part10.00010705.08050302@advantech.com.cn]

-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.gif
Type: image/gif
Size: 2322 bytes
Desc: image001.gif
URL: <http://xenomai.org/pipermail/xenomai/attachments/20180831/fe077f0e/attachment.gif>

Re: [Xenomai] The cyclictest test shows high latencies

[Jan Kiszka]

On 2018-08-31 09:16, zhengguang.yang(杨争光) wrote:
> Dear Xenomai Team:
> I want to use xenomai on imx6q.
> When I install it according to your wiki, then check the kernel boot log:
> 
> # dmesg |grep -i xenomai
> [    0.408274] [Xenomai] scheduling class idle registered.
> [    0.408281] [Xenomai] scheduling class rt registered.
> [    0.408538] I-pipe: head domain Xenomai registered.
> [    0.412129] [Xenomai] Cobalt v3.0.7 (Lingering Dawn)
> 
> However, after testing with cyclictest, it seems that there is no difference between xenomai-linux and non_xenomai-linux.
> 
> 
> ·         Maybe I did something wrong and what goes wrong that leads to this result?
> 

Xenomai in Cobalt mode (dual kernel) is not an API-transparent approach 
like PREEMPT-RT. You need to use an application that is at least 
compiled for Xenomai, typically it should also be adjusted for it.

There is a demo variant of cyclictest in the userspace package of 
Xenomai, and there is the default measurement tool "latency". Don't 
forget to run autotune first. All described in 
https://gitlab.denx.de/Xenomai/xenomai/wikis/Installing_Xenomai_3.

Jan

-- 
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux

[Xenomai] 答复: The cyclictest test shows high latencies

[zhengguang.yang(杨争光)]

Hi Jan:
Thank you for your reply.

Our application has been developed on PREEMPT-RT. Can we apply our application directly to Xenomai_Linux. If not, what we need to pay attention to? 

Do you have a development manual on Xenomai_Linux?


-----邮件原件-----
发件人: Jan Kiszka [mailto:jan.kiszka@siemens.com] 
发送时间: 2018年9月3日 18:33
收件人: zhengguang.yang(杨争光); xenomai@xenomai.org
主题: Re: The cyclictest test shows high latencies

On 2018-08-31 09:16, zhengguang.yang(杨争光) wrote:
> Dear Xenomai Team:
> I want to use xenomai on imx6q.
> When I install it according to your wiki, then check the kernel boot log:
> 
> # dmesg |grep -i xenomai
> [    0.408274] [Xenomai] scheduling class idle registered.
> [    0.408281] [Xenomai] scheduling class rt registered.
> [    0.408538] I-pipe: head domain Xenomai registered.
> [    0.412129] [Xenomai] Cobalt v3.0.7 (Lingering Dawn)
> 
> However, after testing with cyclictest, it seems that there is no difference between xenomai-linux and non_xenomai-linux.
> 
> 
> ・         Maybe I did something wrong and what goes wrong that leads to this result?
> 

Xenomai in Cobalt mode (dual kernel) is not an API-transparent approach like PREEMPT-RT. You need to use an application that is at least compiled for Xenomai, typically it should also be adjusted for it.

There is a demo variant of cyclictest in the userspace package of Xenomai, and there is the default measurement tool "latency". Don't forget to run autotune first. All described in https://gitlab.denx.de/Xenomai/xenomai/wikis/Installing_Xenomai_3.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate Competence Center Embedded Linux

Re: [Xenomai] 答复: The cyclictest test shows high latencies

[Jan Kiszka]

On 2018-09-04 05:28, zhengguang.yang(杨争光) wrote:
> Hi Jan:
> Thank you for your reply.
> 
> Our application has been developed on PREEMPT-RT. Can we apply our application directly to Xenomai_Linux. If not, what we need to pay attention to?
> 
> Do you have a development manual on Xenomai_Linux?
> 

Scan the homepage and the documents in the Xenomai source repository for 
what you are looking for. There are many hints already, maybe not all, 
but that is best pointed out from a (new) user's perspective like you 
have. So please provide feedback afterwards / feel free to ask specific 
questions on what remains unclear!

Jan

> 
> -----邮件原件-----
> 发件人: Jan Kiszka [mailto:jan.kiszka@siemens.com]
> 发送时间: 2018年9月3日 18:33
> 收件人: zhengguang.yang(杨争光); xenomai@xenomai.org
> 主题: Re: The cyclictest test shows high latencies
> 
> On 2018-08-31 09:16, zhengguang.yang(杨争光) wrote:
>> Dear Xenomai Team:
>> I want to use xenomai on imx6q.
>> When I install it according to your wiki, then check the kernel boot log:
>>
>> # dmesg |grep -i xenomai
>> [    0.408274] [Xenomai] scheduling class idle registered.
>> [    0.408281] [Xenomai] scheduling class rt registered.
>> [    0.408538] I-pipe: head domain Xenomai registered.
>> [    0.412129] [Xenomai] Cobalt v3.0.7 (Lingering Dawn)
>>
>> However, after testing with cyclictest, it seems that there is no difference between xenomai-linux and non_xenomai-linux.
>>
>>
>> ·         Maybe I did something wrong and what goes wrong that leads to this result?
>>
> 
> Xenomai in Cobalt mode (dual kernel) is not an API-transparent approach like PREEMPT-RT. You need to use an application that is at least compiled for Xenomai, typically it should also be adjusted for it.
> 
> There is a demo variant of cyclictest in the userspace package of Xenomai, and there is the default measurement tool "latency". Don't forget to run autotune first. All described in https://gitlab.denx.de/Xenomai/xenomai/wikis/Installing_Xenomai_3.
> 
> Jan
> 
> --
> Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate Competence Center Embedded Linux
>