public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Bill Davidsen <davidsen@tmr.com>
To: linux-kernel@vger.kernel.org
Subject: Re: 2.6.1 and irq balancing
Date: Sun, 11 Jan 2004 23:42:27 -0500	[thread overview]
Message-ID: <btt7pt$3m8$1@gatekeeper.tmr.com> (raw)
In-Reply-To: <7F740D512C7C1046AB53446D37200173618820@scsmsx402.sc.intel.com>

Nakajima, Jun wrote:

> 2.6 kernels don't need a patch to it as far as I understand. Are you
> saying that with significant amount of load, you did not see any
> distribution of interrupts? Today's threshold in the kernel is high
> because we found moving around interrupts frequently rather hurt the
> cache and thus lower the performance compared to "do nothing". Can you
> try to create significant load with your network (eth0 and eh1) and see
> what happens? 

How much is significant? The term doesn't really help much. I will say 
that with one NIC taking 120MB/sec of data to a TB database and copying 
to two other machine (~220MB)  my interrupts got up in in the 5k-12k 
range with essentially CPU0 doing the work, some few percent going to CPU2.

I'm not sure this is a problem in any way, but some serious load is 
needed to trigger sharing, if indeed the NIC was the source of the ints 
on CPU2.

2x Xeon-2.4GHz, HT enabled. "CPU2" from memory, it was the other 
physical CPU, not another sibling. Worked fine, didn't break, don't 
regard it as a problem.

-- 
bill davidsen <davidsen@tmr.com>
   CTO TMR Associates, Inc
   Doing interesting things with small computers since 1979

  reply	other threads:[~2004-01-12  4:40 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-01-11 23:59 2.6.1 and irq balancing Nakajima, Jun
2004-01-12  4:42 ` Bill Davidsen [this message]
2004-01-12 14:06   ` Zwane Mwaikambo
2004-01-12 16:10   ` Martin J. Bligh
2004-01-13  6:50 ` Ethan Weinstein
2004-01-13  7:05   ` Nick Piggin
  -- strict thread matches above, loose matches on Subject: below --
2004-01-13  8:09 Nakajima, Jun
2004-01-13  7:57 Nakajima, Jun
2004-01-10 23:14 Ethan Weinstein
2004-01-11  2:39 ` Ed Tomlinson
2004-01-11  3:38   ` Nick Piggin
2004-01-11  9:52     ` Arjan van de Ven
2004-01-11  5:19   ` Ethan Weinstein
2004-01-11  9:51 ` Arjan van de Ven
2004-01-11 16:50   ` Joe Korty
2004-01-11 18:19     ` Arjan van de Ven
2004-01-15 11:43     ` Pavel Machek
2004-01-11 13:14 ` Martin Schlemmer

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='btt7pt$3m8$1@gatekeeper.tmr.com' \
    --to=davidsen@tmr.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