From: jamal <hadi@cyberus.ca>
To: <kuznet@ms2.inr.ac.ru>
Cc: Andreas Dilger <adilger@turbolabs.com>,
<Robert.Olsson@data.slu.se>, <mingo@elte.hu>,
<linux-kernel@vger.kernel.org>, <bcrl@redhat.com>,
<netdev@oss.sgi.com>, <torvalds@transmeta.com>,
<alan@lxorguk.ukuu.org.uk>
Subject: Re: [announce] [patch] limiting IRQ load, irq-rewrite-2.4.11-B5
Date: Mon, 8 Oct 2001 09:58:22 -0400 (EDT) [thread overview]
Message-ID: <Pine.GSO.4.30.0110080948330.5473-100000@shell.cyberus.ca> (raw)
In-Reply-To: <200110051917.XAA23007@ms2.inr.ac.ru>
On Fri, 5 Oct 2001 kuznet@ms2.inr.ac.ru wrote:
> Hello!
>
> > One question which I have is why would you ever want to continue polling
> > if there is no work to be done? Is it a tradeoff between the amount of
> > time to handle an IRQ vs. the time to do a poll?
>
> Yes. IRQ even taken alone eat non-trivial amount of resources.
>
> Actually, I remember Jamal worked with machine, which had
> no io-apic and only irq ack/mask/unmask eated >15% of cpu there. :-)
>
This was Robert actually; conclusion was Interupts are very expensive. If
we can get rid of as many of them as possible, we are getting a side
benefit. I cant find the old data, but Robert has some data over here:
http://robur.slu.se/Linux/net-development/experiments/010301
> "some hysteresis" is right word. This loop is an experiment with still
> unknown result yet. Originally, Jamal proposed to spin several times.
> I killed this.
It was a good idea you killed it, now that i think in retrospect,
The solution is much cleaner without it.
> Robert proposed to check inifinite loop yet. (Note,
> jiffies check is just a way to get rid of completely idle devices,
> one jiffie is enough lonf time to be considered infinite).
>
In my opinion we really dont need this. I did some quick testing, with and
without it and i dont see any differences.
cheers,
jamal
next prev parent reply other threads:[~2001-10-08 14:05 UTC|newest]
Thread overview: 151+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-10-02 0:41 [announce] [patch] limiting IRQ load, irq-rewrite-2.4.11-B5 jamal
2001-10-02 1:04 ` Benjamin LaHaise
2001-10-02 1:54 ` jamal
2001-10-02 5:13 ` Benjamin LaHaise
2001-10-02 5:55 ` Ben Greear
2001-10-03 9:22 ` Ingo Molnar
2001-10-03 14:06 ` David Brownell
2001-10-02 12:10 ` jamal
2001-10-02 22:00 ` jamal
2001-10-03 8:34 ` Ingo Molnar
2001-10-03 9:29 ` Helge Hafting
2001-10-03 12:49 ` jamal
2001-10-03 14:51 ` Ingo Molnar
2001-10-03 15:14 ` jamal
2001-10-03 17:28 ` Ingo Molnar
2001-10-04 0:53 ` jamal
2001-10-04 6:28 ` Ingo Molnar
2001-10-04 11:34 ` jamal
2001-10-04 17:40 ` Andreas Dilger
2001-10-04 18:33 ` jamal
2001-10-04 6:50 ` Ben Greear
2001-10-04 6:52 ` Ingo Molnar
2001-10-04 11:50 ` jamal
2001-10-04 6:55 ` Jeff Garzik
2001-10-04 6:56 ` Ingo Molnar
2001-10-04 21:28 ` Alex Bligh - linux-kernel
2001-10-04 21:49 ` Benjamin LaHaise
2001-10-04 23:20 ` Alex Bligh - linux-kernel
2001-10-04 23:26 ` Benjamin LaHaise
2001-10-04 23:47 ` Robert Love
2001-10-04 23:51 ` Linus Torvalds
2001-10-05 0:00 ` Ben Greear
2001-10-05 0:18 ` Davide Libenzi
2001-10-05 2:01 ` jamal
2001-10-04 22:01 ` Simon Kirby
2001-10-04 23:25 ` Alex Bligh - linux-kernel
2001-10-04 23:34 ` Simon Kirby
2001-10-04 22:10 ` Alan Cox
2001-10-04 23:28 ` Alex Bligh - linux-kernel
2001-10-05 15:22 ` Robert Olsson
2001-10-03 9:38 ` Ingo Molnar
2001-10-03 13:03 ` jamal
2001-10-03 13:25 ` jamal
2001-10-03 15:28 ` Ingo Molnar
2001-10-03 15:56 ` jamal
2001-10-03 16:51 ` Ingo Molnar
2001-10-04 0:46 ` jamal
2001-10-08 0:31 ` Andrea Arcangeli
2001-10-08 4:58 ` Bernd Eckenfels
2001-10-08 15:00 ` Alan Cox
2001-10-08 15:03 ` Jeff Garzik
2001-10-08 15:12 ` Alan Cox
2001-10-08 15:09 ` jamal
2001-10-08 15:22 ` Alan Cox
2001-10-08 15:20 ` jamal
2001-10-08 15:35 ` Alan Cox
2001-10-08 15:57 ` jamal
2001-10-08 16:11 ` Alan Cox
2001-10-08 16:11 ` jamal
2001-10-10 16:26 ` Pavel Machek
2001-10-10 16:25 ` Pavel Machek
2001-10-08 15:24 ` Andrea Arcangeli
2001-10-08 15:35 ` Alan Cox
2001-10-08 15:19 ` Andrea Arcangeli
2001-10-08 15:10 ` bill davidsen
2001-10-03 21:08 ` Robert Olsson
2001-10-03 22:22 ` Andreas Dilger
2001-10-04 17:32 ` Davide Libenzi
2001-10-05 14:52 ` Robert Olsson
2001-10-05 18:48 ` Andreas Dilger
2001-10-05 19:07 ` Davide Libenzi
2001-10-05 19:17 ` kuznet
2001-10-08 13:58 ` jamal [this message]
2001-10-08 17:42 ` Robert Olsson
2001-10-08 17:39 ` jamal
2001-10-07 6:11 ` Robert Olsson
2001-10-03 16:53 ` kuznet
2001-10-03 17:06 ` Ingo Molnar
2001-10-04 0:44 ` jamal
2001-10-04 6:35 ` Ingo Molnar
2001-10-04 11:41 ` jamal
2001-10-05 16:42 ` kuznet
2001-10-04 13:05 ` Robert Olsson
2001-10-03 19:03 ` Benjamin LaHaise
2001-10-04 1:10 ` jamal
2001-10-04 1:30 ` Benjamin LaHaise
2001-10-03 22:31 ` Rob Landley
2001-10-04 1:39 ` jamal
2001-10-03 15:42 ` Ben Greear
2001-10-03 15:58 ` jamal
2001-10-03 16:09 ` Ben Greear
2001-10-03 16:14 ` Ingo Molnar
2001-10-03 16:20 ` Jeff Garzik
2001-10-03 16:33 ` Linus Torvalds
2001-10-03 17:25 ` Ingo Molnar
2001-10-03 18:11 ` Linus Torvalds
2001-10-03 20:41 ` Jeremy Hansen
2001-10-03 20:02 ` Simon Kirby
2001-10-04 1:04 ` jamal
2001-10-04 6:47 ` Ben Greear
2001-10-04 7:41 ` Henning P. Schmiedehausen
2001-10-04 16:09 ` Ben Greear
2001-10-04 17:32 ` Henning P. Schmiedehausen
2001-10-04 18:03 ` Ben Greear
2001-10-04 18:30 ` Christopher E. Brown
2001-10-04 11:47 ` jamal
2001-10-04 15:56 ` Ben Greear
2001-10-04 18:23 ` jamal
2001-10-04 6:50 ` Ingo Molnar
2001-10-04 11:49 ` jamal
2001-10-04 8:45 ` Simon Kirby
2001-10-04 11:54 ` jamal
2001-10-04 15:03 ` Tim Hockin
2001-10-04 18:55 ` Ion Badulescu
2001-10-04 19:00 ` jamal
2001-10-04 21:16 ` Ion Badulescu
2001-10-04 4:12 ` bill davidsen
2001-10-04 18:16 ` Alan Cox
2001-10-03 13:38 ` Robert Olsson
2001-10-04 21:22 ` Alex Bligh - linux-kernel
2001-10-05 14:32 ` Robert Olsson
2001-10-03 8:38 ` Ingo Molnar
2001-10-04 3:50 ` bill davidsen
2001-10-02 17:03 ` Robert Olsson
2001-10-02 17:37 ` jamal
2001-10-02 19:46 ` Andreas Dilger
-- strict thread matches above, loose matches on Subject: below --
2001-10-08 14:45 jamal
2001-10-09 0:36 ` Scott Laird
2001-10-09 3:17 ` jamal
2001-10-09 4:04 ` Werner Almesberger
2001-10-04 8:25 Magnus Redin
2001-10-04 11:39 ` Trever L. Adams
[not found] <200110031811.f93IBoN10026@penguin.transmeta.com>
2001-10-03 18:23 ` Ingo Molnar
2001-10-04 9:19 ` BALBIR SINGH
2001-10-04 9:22 ` Ingo Molnar
2001-10-04 9:49 ` BALBIR SINGH
2001-10-04 10:25 ` Ingo Molnar
2001-10-07 20:37 ` Andrea Arcangeli
2001-10-03 14:15 Manfred Spraul
2001-10-03 15:09 ` jamal
2001-10-03 18:37 ` Davide Libenzi
2001-10-01 22:16 Ingo Molnar
2001-10-01 22:26 ` Tim Hockin
2001-10-01 22:50 ` Ingo Molnar
2001-10-01 22:36 ` Andreas Dilger
2001-10-01 22:50 ` Ben Greear
2001-10-02 14:30 ` Alan Cox
2001-10-02 20:51 ` Ingo Molnar
2001-10-01 23:03 ` Linus Torvalds
2001-10-02 6:50 ` Marcus Sundberg
2001-10-03 8:47 ` Ingo Molnar
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=Pine.GSO.4.30.0110080948330.5473-100000@shell.cyberus.ca \
--to=hadi@cyberus.ca \
--cc=Robert.Olsson@data.slu.se \
--cc=adilger@turbolabs.com \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=bcrl@redhat.com \
--cc=kuznet@ms2.inr.ac.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=netdev@oss.sgi.com \
--cc=torvalds@transmeta.com \
/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;
as well as URLs for NNTP newsgroup(s).