From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Karl Tyss <tyss.k@domain.hid>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai-help] IRQ-Latency when in idle State on ARM
Date: Fri, 05 Jun 2009 13:10:24 +0200 [thread overview]
Message-ID: <4A28FD20.1020400@domain.hid> (raw)
In-Reply-To: <4A2907EF.3E52.00F8.0@domain.hid>
Karl Tyss wrote:
> Hi,
>
> thank you for the quick answer.
>
> The idea with deactivating the caches is to see if they are influencing
> this behavior. I also tried out the FCSE option and it did not help. My
> issue is that if there is a user space application that starts lots of
> short processes/threads and sleeps for a short time, in this case I get
> a large jitter. Till this point I was able to find out that it makes a
> difference if the idle task is running.
How large ? If it is something around 200us it is normal for an ARM.
Note that the cache flush is not alone, there is also a TLB flush. If
you do not want the TLB flush, then you will have to run ucLinux.
--
Gilles.
next prev parent reply other threads:[~2009-06-05 11:10 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <4A28F029020000F80002DB14@domain.hid>
[not found] ` <4A28FAD4020000F80002DB27@domain.hid>
2009-06-05 9:00 ` [Xenomai-help] IRQ-Latency when in idle State on ARM Karl Tyss
2009-06-05 9:31 ` Gilles Chanteperdrix
2009-06-05 9:56 ` Karl Tyss
2009-06-05 11:10 ` Gilles Chanteperdrix [this message]
2009-06-05 13:42 ` Gilles Chanteperdrix
2009-06-05 14:09 ` Karl Tyss
2009-06-05 14:16 ` Gilles Chanteperdrix
2009-06-05 14:17 ` Gilles Chanteperdrix
2009-06-05 14:49 ` Karl Tyss
2009-06-05 15:01 ` Gilles Chanteperdrix
2009-06-05 12:13 ` Bosko Radivojevic
2009-06-08 7:31 ` Karl Tyss
2009-06-05 17:36 Karl Tyss
[not found] <4A294F59020000F80002DC0E@msw.eppendorf.de>
[not found] ` <200906051932.16827.karl.tyss@domain.hid>
2009-06-05 18:09 ` Gilles Chanteperdrix
2009-06-05 19:08 ` Gilles Chanteperdrix
2009-06-06 17:38 ` Karl Tyss
2009-06-06 18:00 ` 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=4A28FD20.1020400@domain.hid \
--to=gilles.chanteperdrix@xenomai.org \
--cc=tyss.k@domain.hid \
--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.