public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Stephen Samuel <samuel@bcgreen.com>
To: "Wessler, Siegfried" <Siegfried.Wessler@de.hbm.com>,
	linux-kernel@vger.kernel.org
Subject: Re: interrupt latency
Date: Tue, 27 Aug 2002 07:11:58 -0700	[thread overview]
Message-ID: <3D6B88AE.8010206@bcgreen.com> (raw)
In-Reply-To: D3524C0FFDC6A54F9D7B6BBEECD341D5D56FDB@HBMNTX0.da.hbm.com

http://www.linux.org/dist/index.html contains an index to a number of
Linux distributions.  Check out the embeded kernels. They include some
Realtime mods. As an example, RTLinux claims to do hard realtime by
running the Linux kernel as it's lowest priority task. This is supposed
to allow serious realtime work without having to mess too much with
the kernel.

Wessler, Siegfried wrote:
> Hello,
> 
> I am running and will in near future kernel 2.4.18 on an embedded system.
> 
> I have to speed up interrupt latency and need to understand how in what
> timing tasklets are called and arbitraded.
  .....
> What's behind it: We patched NMI and do some stuff we have to do very
> regularly in there. After NMI we have to quiet fast start a kernel or even a
> user space function with low latency. Also I measured 8 milliseconds after a
> hardware interrupt before the corresponding interrupt function is called. At
> RTI time it is even longer (around 12 microseconds). Need to find a way to
> exactly understand why, and maybe speed up a bit.
-- 
Stephen Samuel +1(604)876-0426                samuel@bcgreen.com
		   http://www.bcgreen.com/~samuel/
Powerful committed communication, reaching through fear, uncertainty and
doubt to touch the jewel within each person and bring it to life.


  reply	other threads:[~2002-08-27 14:07 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-08-27  9:58 interrupt latency Wessler, Siegfried
2002-08-27 14:11 ` Stephen Samuel [this message]
2002-08-27 17:16   ` Robert Schwebel
2002-08-27 21:44     ` Stephen Samuel
2002-08-27 17:41 ` Mark Hounschell
2002-08-27 18:01   ` Richard B. Johnson
2002-08-27 19:54     ` yodaiken
2002-08-27 20:44       ` Richard B. Johnson
2002-08-27 20:56         ` yodaiken
2002-08-27 22:47           ` Rogier Wolff
2002-08-28 12:18           ` Richard B. Johnson
2002-08-28 13:41             ` yodaiken
2002-08-28 14:25               ` Jonathan Lundell
2002-08-28 13:53             ` yodaiken
2002-08-28 15:02               ` Richard B. Johnson
2002-08-28 15:19                 ` yodaiken
2002-08-28 15:31                 ` Alan Cox
2002-08-28 15:37                   ` Richard B. Johnson
2002-08-28 16:53                   ` Randy.Dunlap
2002-08-28 12:42         ` Pavel Machek
2002-08-27 18:05 ` Dag Nygren
  -- strict thread matches above, loose matches on Subject: below --
2002-10-30 23:50 Keith Adamson

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=3D6B88AE.8010206@bcgreen.com \
    --to=samuel@bcgreen.com \
    --cc=Siegfried.Wessler@de.hbm.com \
    --cc=linux-kernel@vger.kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox