From: Wolfgang Grandegger <wg@grandegger.com>
To: Robert Schwebel <r.schwebel@pengutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>,
linux-rt-users@vger.kernel.org, John Stultz <johnstul@us.ibm.com>
Subject: Re: High latencies on MPC5200 with patch-2.6.24-rc5-rt1
Date: Thu, 10 Jan 2008 22:49:58 +0100 [thread overview]
Message-ID: <47869306.8000308@grandegger.com> (raw)
In-Reply-To: <20080110162351.GN3177@pengutronix.de>
Robert Schwebel wrote:
> On Thu, Jan 10, 2008 at 03:35:27PM +0100, Robert Schwebel wrote:
>>> Could you run your cyclictest much longer?
>> I'll re-test with your parameters.
>
> Done, here are the results (data and histogram):
>
> http://www.pengutronix.de/software/realtime-preempt/20080110-1-cyclictest/20080110-1-phyCORE-MPC5200B-tiny-data.png
> http://www.pengutronix.de/software/realtime-preempt/20080110-1-cyclictest/20080110-1-phyCORE-MPC5200B-tiny-histo.png
>
> Especially the data plot is interesting: it shows that most of the shots
> are below 80 us, but there are regular peaks. If you look carefully, you
> also see that the peaks are "growing", which usually means that there is
> some interference.
A latency peak every 16.6 second, hm, interesting.
> Time to activate latency hunting...
Unfortunately, the latency tracer of the -rt kernel is not available for
PowerPC.
Wolfgang.
next prev parent reply other threads:[~2008-01-10 21:50 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-01-08 10:13 High latencies on MPC5200 with patch-2.6.24-rc5-rt1 Wolfgang Grandegger
2008-01-08 15:49 ` Robert Schwebel
2008-01-08 16:41 ` Wolfgang Grandegger
2008-01-08 20:40 ` Robert Schwebel
2008-01-08 21:25 ` Juergen Beisert
2008-01-09 9:03 ` Robert Schwebel
2008-01-09 9:50 ` Wolfgang Grandegger
2008-01-09 14:08 ` Robert Schwebel
2008-01-09 22:51 ` Robert Schwebel
2008-01-10 0:01 ` Robert Schwebel
2008-01-10 13:17 ` Wolfgang Grandegger
2008-01-10 14:35 ` Robert Schwebel
2008-01-10 16:23 ` Robert Schwebel
2008-01-10 21:27 ` Robert Schwebel
2008-01-10 21:49 ` Wolfgang Grandegger [this message]
2008-01-10 15:48 ` Juergen Beisert
2008-01-11 9:22 ` Wolfgang Grandegger
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=47869306.8000308@grandegger.com \
--to=wg@grandegger.com \
--cc=johnstul@us.ibm.com \
--cc=linux-rt-users@vger.kernel.org \
--cc=r.schwebel@pengutronix.de \
--cc=tglx@linutronix.de \
/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.