All of lore.kernel.org
 help / color / mirror / Atom feed
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: 嵌入式工程师 <ericvic@163.com>
Cc: "xenomai@xenomai.org" <xenomai@xenomai.org>
Subject: Re: [Xenomai] imx6q xenomai ipipe-3.0-imx6q
Date: Wed, 02 Apr 2014 09:28:10 +0200	[thread overview]
Message-ID: <533BBC0A.7050601@xenomai.org> (raw)
In-Reply-To: <4e1f2397.14cae.1451fed778d.Coremail.ericvic@163.com>

On 04/02/2014 02:53 AM, 嵌入式工程师 wrote:
> I know latency test can not run with e other real-time  activity, but
> my program will run some real-time activties at the same time ,now it
> looks  like because multiple cpu shared memory causes a great
> difference jitter .

That is not your problem. Your problem is that if you run a task with
priority 99 on the same cpu as the latency test, the time this task
prevents the latency test from running is counted by the latency test as
latency, which gives wrong results. This is not latency, this is simply
the scheduler doing its job: letting a task running until it suspends
before letting the latency task running. That is because the two tasks
have the same priority.

-- 
                                                                Gilles.


  reply	other threads:[~2014-04-02  7:28 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-01  2:35 [Xenomai] imx6q xenomai ipipe-3.0-imx6q 嵌入式工程师
2014-04-01 10:49 ` Gilles Chanteperdrix
2014-04-02  0:53   ` 嵌入式工程师
2014-04-02  7:28     ` Gilles Chanteperdrix [this message]
2014-04-03 10:25       ` 嵌入式工程师
  -- strict thread matches above, loose matches on Subject: below --
2014-04-18 10:28 嵌入式工程师
2014-04-18 11:47 ` Gilles Chanteperdrix
2014-04-20  5:06   ` eric
2014-04-20  9:03     ` Gilles Chanteperdrix
2014-04-20  9:23       ` Gilles Chanteperdrix
2014-04-20 10:46         ` eric
2014-04-23  4:40           ` eric
2014-04-23 12:24             ` Gilles Chanteperdrix
2014-04-17  8:13 嵌入式工程师
2014-04-17  7:58 嵌入式工程师
2014-04-17  7:43 嵌入式工程师
2014-04-17 11:42 ` Gilles Chanteperdrix
2014-03-26 11:36 嵌入式工程师
2014-03-26 11:50 ` Gilles Chanteperdrix
2014-03-26 13:31   ` 嵌入式工程师
2014-03-26 13:34     ` Gilles Chanteperdrix
2014-03-26 14:29       ` 嵌入式工程师
2014-03-26 23:09         ` Gilles Chanteperdrix
2014-03-27  1:41           ` 嵌入式工程师
2014-03-27  5:24           ` 嵌入式工程师
2014-03-27 12:27             ` Gilles Chanteperdrix
2014-03-28  5:02               ` 嵌入式工程师
2014-03-28 17:35                 ` Gilles Chanteperdrix
2014-03-29  5:54                   ` 嵌入式工程师
2014-03-28  8:19               ` 嵌入式工程师
2014-03-28 17:37                 ` Gilles Chanteperdrix
2014-03-28  9:08               ` 嵌入式工程师
2014-03-28 17:38                 ` Gilles Chanteperdrix
2014-03-29  6:21                   ` 嵌入式工程师
2014-03-29 13:51                     ` Gilles Chanteperdrix

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=533BBC0A.7050601@xenomai.org \
    --to=gilles.chanteperdrix@xenomai.org \
    --cc=ericvic@163.com \
    --cc=xenomai@xenomai.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.