From: "David S. Miller" <davem@redhat.com>
To: davej@codemonkey.org.uk
Cc: andrea@suse.de, akpm@digeo.com, davidsen@tmr.com,
haveblue@us.ibm.com, habanero@us.ibm.com, mbligh@aracnet.com,
linux-kernel@vger.kernel.org
Subject: Re: userspace irq balancer
Date: Mon, 26 May 2003 18:17:34 -0700 (PDT) [thread overview]
Message-ID: <20030526.181734.68129361.davem@redhat.com> (raw)
In-Reply-To: <20030527011620.GB7135@suse.de>
From: Dave Jones <davej@codemonkey.org.uk>
Date: Tue, 27 May 2003 02:16:20 +0100
On Tue, May 27, 2003 at 03:09:03AM +0200, Andrea Arcangeli wrote:
> rdtsc could do it very well, irqs and softirqs can't be rescheduled so
> you can tick measure how long you take in each cpu
On CPUs that vary frequency, this will break, unless TSC scales
with frequency. You cannot assume that this will be the case.
This is an important issue, for another reason.
The networking packet scheduler layer wants an accurate (but
cheap) high frequency time source too.
I keep forgetting to go back and deal with fixing up all of
those hairy macros in pkt_sched.h, I've added this to my TODO
list.
next prev parent reply other threads:[~2003-05-27 1:09 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-05-21 21:43 userspace irq balancer Nakajima, Jun
2003-05-22 0:29 ` Gerrit Huizenga
2003-05-22 1:28 ` Martin J. Bligh
2003-05-22 1:44 ` Gerrit Huizenga
2003-05-22 2:03 ` William Lee Irwin III
2003-05-22 2:04 ` William Lee Irwin III
2003-05-22 2:12 ` Zwane Mwaikambo
2003-05-22 3:57 ` Martin J. Bligh
2003-05-22 17:24 ` Bill Davidsen
2003-05-22 22:44 ` David S. Miller
2003-05-26 22:24 ` Andrea Arcangeli
2003-05-26 23:26 ` Andrew Morton
2003-05-26 23:34 ` Andrea Arcangeli
2003-05-26 23:43 ` David S. Miller
[not found] ` <20030527000639.GA3767@dualathlon.random>
2003-05-27 0:15 ` David S. Miller
2003-05-27 0:41 ` Andrea Arcangeli
2003-05-27 0:48 ` David S. Miller
2003-05-27 1:09 ` Andrea Arcangeli
2003-05-27 1:13 ` David S. Miller
2003-05-27 1:26 ` Andrea Arcangeli
2003-05-27 6:11 ` David S. Miller
2003-05-27 11:53 ` Andrea Arcangeli
2003-05-27 22:04 ` David S. Miller
2003-05-27 22:27 ` Andrea Arcangeli
2003-05-27 23:55 ` David S. Miller
2003-06-13 6:22 ` David S. Miller
2003-06-13 18:23 ` Andrea Arcangeli
2003-05-27 1:16 ` Dave Jones
2003-05-27 1:17 ` David S. Miller [this message]
2003-05-27 9:07 ` Arjan van de Ven
2003-05-27 9:10 ` David S. Miller
2003-05-27 1:28 ` Andrea Arcangeli
2003-05-27 1:53 ` William Lee Irwin III
2003-05-27 1:59 ` Andrew Morton
2003-05-27 2:10 ` William Lee Irwin III
2003-05-27 2:15 ` Zwane Mwaikambo
2003-05-27 2:44 ` William Lee Irwin III
2003-05-27 2:45 ` Zwane Mwaikambo
2003-05-27 4:22 ` William Lee Irwin III
2003-05-27 2:15 ` Andrea Arcangeli
2003-05-27 2:14 ` Andrea Arcangeli
2003-05-27 2:26 ` William Lee Irwin III
2003-05-27 1:17 ` Andrea Arcangeli
2003-05-27 1:20 ` David S. Miller
2003-05-27 1:33 ` Andrea Arcangeli
2003-05-22 14:18 ` James Cleverdon
2003-05-22 14:43 ` William Lee Irwin III
2003-05-22 15:30 ` James Cleverdon
2003-05-22 15:45 ` William Lee Irwin III
-- strict thread matches above, loose matches on Subject: below --
2003-05-24 1:10 Nakajima, Jun
2003-05-21 16:31 James Bottomley
2003-05-21 20:16 ` Arjan van de Ven
2003-05-20 15:41 Nakajima, Jun
2003-05-21 13:54 ` James Cleverdon
2003-05-21 22:56 ` Zwane Mwaikambo
[not found] <200305191314.06216.pbadari@us.ibm.com>
2003-05-19 22:07 ` Dave Hansen
2003-05-19 22:11 ` Arjan van de Ven
2003-05-19 22:22 ` Dave Hansen
2003-05-20 3:25 ` David S. Miller
2003-05-20 3:46 ` William Lee Irwin III
2003-05-20 5:03 ` Dave Hansen
2003-05-20 5:53 ` Martin J. Bligh
2003-05-20 6:13 ` David S. Miller
2003-05-20 6:36 ` Dave Hansen
2003-05-20 6:40 ` David S. Miller
2003-05-20 14:07 ` Andrew Theurer
2003-05-20 14:21 ` Jeff Garzik
2003-05-20 14:35 ` Andrew Theurer
[not found] ` <20030520.163833.104040023.davem@redhat.com>
2003-05-21 14:58 ` Martin J. Bligh
2003-05-21 22:55 ` David S. Miller
2003-05-21 11:00 ` Kai Bankett
2003-05-20 14:01 ` Martin J. Bligh
2003-05-20 9:00 ` Arjan van de Ven
2003-05-20 9:14 ` William Lee Irwin III
2003-05-20 9:17 ` Andrew Morton
[not found] ` <20030520.172230.102567463.davem@redhat.com>
2003-05-21 14:27 ` James Cleverdon
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=20030526.181734.68129361.davem@redhat.com \
--to=davem@redhat.com \
--cc=akpm@digeo.com \
--cc=andrea@suse.de \
--cc=davej@codemonkey.org.uk \
--cc=davidsen@tmr.com \
--cc=habanero@us.ibm.com \
--cc=haveblue@us.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mbligh@aracnet.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