All of lore.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 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.