答复: linux4.14+xenomai3.1 real-time

夏侯量 xia.h.l at lynuc.cn
Fri Apr 17 12:23:55 CEST 2020


ok,thanks.

-----邮件原件-----
发件人: Jan Kiszka [mailto:jan.kiszka at siemens.com] 
发送时间: 2020年4月17日 17:50
收件人: 夏侯量; xenomai at xenomai.org
抄送: huang.c.h at lynuc.cn
主题: Re: linux4.14+xenomai3.1 real-time

Hi Xiahou Liang,

On 17.04.20 11:36, 夏侯量 via Xenomai wrote:
> dear Xenomai Team:
> 
> When we tested on the Intel(r) Celeron(r) processor 1047ue (third
> generation) motherboard (using kernel version: 4.1.18, xenomai version: 2.6.
> 5, patch: ipipe-core-4.1.18-x86-3. ), The real-time test results meet 
> the requirements.But the 4.1.18 version of the kernel (xenomai version 
> 2.6.5) running on the Intel(r) Celeron(r) processor 3955U (sixth 
> generation) motherboard can not guarantee real-time performance
> 
> And on Intel(r) Celeron(r) processor 3955U (sixth generation) 
> motherboard (kernel version: 4.14.134, xenomai version: 3.1, patch:
> ipipe-core-4.14.134-x86-2. Patch ), We have done many configuration 
> modification tests. However, the maximum jitter is 25u under 1ms, the

IOW, the maximum jitter was 975 µs? That would be indeed completely off.

> real-time test results cannot meet our requirements. Our goal is a 
> maximum jitter of around 10u.

How did  you measure the latency? Via the Xenomai testsuite (latency) or via your own application? If the latter, can you reproduce such excessive latencies also with Xenomai tests?

> 
> We would like to ask what relevant content needs to be modified.
> 

First of all, don't use 4.14 anymore when starting a new project. It's unmaintained Xenomai-wise. Please try with latest 4.19 patch (ipipe-core-4.19.114-cip24-x86-12).

Then we would need your kernel .config for that setup if you can still reproduce that high latency.

Jan

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




More information about the Xenomai mailing list