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From: 박재호 <jaeho@seoultech.ac.kr>
To: xenomai@xenomai.org
Subject: [Xenomai] What does activating SMP mean?
Date: Mon, 1 Oct 2018 14:33:43 +0900 (KST)	[thread overview]
Message-ID: <759115071.1538372023382.JavaMail.root@webmail> (raw)

Hi, all



I thought that activating SMP makes tasks using all cpu cores, but I realized that it doesn't.

I did not explicitly specify the CPU when I created the task.

I have created two xenomai tasks and checked to see how much cpu share the task has on any cpu with / proc / xenomai / stat.

As a result, we confirmed that only one cpu of two cpu works.



So we used T_CPU () to allocate different CPU cores for each task when we created the task.

As a result, you can see that both tasks are running on two CPUs.



I expected to use both CPUs when I enabled SMP, but I did not. Why is not it?

Also, does one task only run on one cpu?





The environment I used is shown below.

------------------------------------------------------------------------

zybo-z7-20(zynq-7000)

Dual-Core ARM Coretex-A9 MPCore Up to 866MHz



xenomai 2.6.5

kernel 3.14.2

ubuntu 14.04

------------------------------------------------------------------------



thank you for your advice.


             reply	other threads:[~2018-10-01  5:33 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-01  5:33 박재호 [this message]
2018-10-01  7:42 ` [Xenomai] What does activating SMP mean? Per Oberg
2018-10-01  7:48   ` Jan Kiszka

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