From: Willy Tarreau <willy@w.ods.org>
To: Karsten Desler <kdesler@soohrt.org>
Cc: P@draigBrady.com, "David S. Miller" <davem@davemloft.net>,
netdev@oss.sgi.com, linux-kernel@vger.kernel.org
Subject: Re: _High_ CPU usage while routing (mostly) small UDP packets
Date: Wed, 8 Dec 2004 06:39:53 +0100 [thread overview]
Message-ID: <20041208053953.GC17946@alpha.home.local> (raw)
In-Reply-To: <20041207112139.GA3610@soohrt.org>
On Tue, Dec 07, 2004 at 12:21:39PM +0100, Karsten Desler wrote:
> > I also notice that a lot of time is spent allocating
> > and freeing the packet buffers (and possible hidden
> > time due to cache misses due to allocating on one
> > CPU and freeing on another?).
> > How many [RT]xDescriptors do you have configured by the way?
>
> 256. I increased them to 1024 shortly after the profiling run, but
> didn't notice any change in the cpu usage (will try again with cyclesoak).
Have you checked the interrupts rate ? I had an e1000 eating many CPU cycles
because it would generate 50000 interrupts/s. Passing the module
InterruptThrottleRate=5000 definitely calmed it down, and more than doubled
the data rate.
Regards
Willy
next prev parent reply other threads:[~2004-12-08 5:39 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-12-06 20:53 _High_ CPU usage while routing (mostly) small UDP packets Karsten Desler
2004-12-06 21:48 ` David S. Miller
2004-12-06 22:41 ` Karsten Desler
2004-12-06 23:56 ` Con Kolivas
2004-12-07 0:18 ` Karsten Desler
[not found] ` <E1CbSf8-00047p-00@calista.eckenfels.6bone.ka-ip.net>
2004-12-07 0:20 ` Karsten Desler
2004-12-07 2:46 ` jamal
2004-12-07 2:54 ` Karsten Desler
2004-12-07 3:18 ` jamal
2004-12-07 3:24 ` Karsten Desler
2004-12-07 3:30 ` jamal
2004-12-07 4:02 ` Karsten Desler
2004-12-07 10:21 ` Karsten Desler
2004-12-07 12:34 ` jamal
2004-12-07 13:14 ` Karsten Desler
2004-12-07 10:47 ` P
2004-12-07 11:21 ` Karsten Desler
2004-12-07 12:38 ` Robert Olsson
2004-12-07 12:50 ` Karsten Desler
2004-12-07 13:04 ` jamal
2004-12-07 13:11 ` Karsten Desler
2004-12-07 13:39 ` P
2004-12-07 18:38 ` Karsten Desler
2004-12-08 5:39 ` Willy Tarreau [this message]
2004-12-08 13:08 ` Karsten Desler
2004-12-08 13:27 ` jamal
2004-12-07 21:10 ` Karsten Desler
2004-12-07 22:40 ` Robert Olsson
2004-12-08 22:06 ` Karsten Desler
2004-12-08 4:31 ` jamal
2004-12-08 13:26 ` Karsten Desler
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=20041208053953.GC17946@alpha.home.local \
--to=willy@w.ods.org \
--cc=P@draigBrady.com \
--cc=davem@davemloft.net \
--cc=kdesler@soohrt.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@oss.sgi.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).