From: Bill Fink <billfink@mindspring•com>
To: Rick Jones <rick.jones2@hp•com>
Cc: Larry McVoy <lm@bitmover•com>,
Linus Torvalds <torvalds@linux-foundation•org>,
davem@davemloft•net, wscott@bitmover•com, netdev@vger•kernel.org
Subject: Re: tcp bw in 2.6
Date: Wed, 3 Oct 2007 03:19:06 -0400 [thread overview]
Message-ID: <20071003031906.5f0d7cfd.billfink@mindspring.com> (raw)
In-Reply-To: <47027C63.803@hp.com>
Tangential aside:
On Tue, 02 Oct 2007, Rick Jones wrote:
> *) depending on the quantity of CPU around, and the type of test one is running,
> results can be better/worse depending on the CPU to which you bind the
> application. Latency tends to be best when running on the same core as takes
> interrupts from the NIC, bulk transfer can be better when running on a different
> core, although generally better when a different core on the same chip. These
> days the throughput stuff is more easily seen on 10G, but the netperf service
> demand changes are still visible on 1G.
Interesting. I was going to say that I've generally had the opposite
experience when it comes to bulk data transfers, which is what I would
expect due to CPU caching effects, but that perhaps it's motherboard/NIC/
driver dependent. But in testing I just did I discovered it's even
MTU dependent (most of my normal testing is always with 9000-byte
jumbo frames).
With Myricom 10-GigE NICs, NIC interrupts on CPU 0 and nuttcp app
running on CPU 1 (both transmit and receive sides), and using 9000-byte
jumbo frames:
[root@lang2 ~]# nuttcp -w10m 192.168.88.16
10078.5000 MB / 10.02 sec = 8437.5396 Mbps 100 %TX 99 %RX
With Myricom 10-GigE NICs, and both NIC interrupts and nuttcp app
on CPU 0 (both transmit and receive sides), again using 9000-byte
jumbo frames:
[root@lang2 ~]# nuttcp -w10m 192.168.88.16
11817.8750 MB / 10.00 sec = 9909.7537 Mbps 100 %TX 74 %RX
Same tests repeated with standard 1500-byte Ethernet MTU:
With Myricom 10-GigE NICs, NIC interrupts on CPU 0 and nuttcp app
running on CPU 1 (both transmit and receive sides), and using
standard 1500-byte Ethernet MTU:
[root@lang2 ~]# nuttcp -M1460 -w10m 192.168.88.16
5685.9375 MB / 10.00 sec = 4768.0951 Mbps 99 %TX 98 %RX
With Myricom 10-GigE NICs, and both NIC interrupts and nuttcp app
on CPU 0 (both transmit and receive sides), again using standard
1500-byte Ethernet MTU:
[root@lang2 ~]# nuttcp -M1460 -w10m 192.168.88.16
4974.0625 MB / 10.03 sec = 4161.6015 Mbps 100 %TX 100 %RX
Now back to your regularly scheduled programming. :-)
-Bill
next prev parent reply other threads:[~2007-10-03 7:19 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20070929142517.EC6AB5FB21@work.bitmover.com>
[not found] ` <alpine.LFD.0.999.0709290914410.3579@woody.linux-foundation.org>
[not found] ` <20070929172639.GB7037@bitmover.com>
[not found] ` <alpine.LFD.0.999.0709291050200.3579@woody.linux-foundation.org>
2007-10-02 0:59 ` tcp bw in 2.6 Larry McVoy
2007-10-02 2:14 ` Linus Torvalds
2007-10-02 2:20 ` Larry McVoy
2007-10-02 3:50 ` David Miller
2007-10-02 4:23 ` Larry McVoy
2007-10-02 15:06 ` John Heffner
2007-10-02 17:14 ` Rick Jones
2007-10-02 17:20 ` Larry McVoy
2007-10-02 18:01 ` Rick Jones
2007-10-02 18:40 ` Larry McVoy
2007-10-02 19:47 ` Rick Jones
2007-10-02 21:32 ` David Miller
2007-10-03 7:19 ` Bill Fink [this message]
2007-10-02 10:52 ` Herbert Xu
2007-10-02 15:09 ` Larry McVoy
2007-10-02 15:41 ` Larry McVoy
2007-10-02 16:25 ` Larry McVoy
2007-10-02 16:47 ` Stephen Hemminger
2007-10-02 16:49 ` Larry McVoy
2007-10-02 17:10 ` Stephen Hemminger
2007-10-15 12:40 ` Daniel Schaffrath
2007-10-15 15:49 ` Stephen Hemminger
2007-10-02 16:34 ` Linus Torvalds
2007-10-02 16:48 ` Larry McVoy
2007-10-02 21:16 ` David Miller
2007-10-02 21:26 ` Larry McVoy
2007-10-02 21:47 ` David Miller
2007-10-02 22:17 ` Rick Jones
2007-10-02 22:32 ` David Miller
2007-10-02 22:36 ` Larry McVoy
2007-10-02 22:59 ` Rick Jones
2007-10-03 8:02 ` David Miller
2007-10-02 16:48 ` Ben Greear
2007-10-02 17:11 ` Larry McVoy
2007-10-02 17:18 ` Ben Greear
2007-10-02 17:21 ` Larry McVoy
2007-10-02 17:54 ` Stephen Hemminger
2007-10-02 18:35 ` Larry McVoy
2007-10-02 18:29 ` John Heffner
2007-10-02 19:07 ` Larry McVoy
2007-10-02 19:29 ` Linus Torvalds
2007-10-02 20:31 ` David Miller
2007-10-02 19:33 ` Larry McVoy
2007-10-02 19:53 ` John Heffner
2007-10-02 20:14 ` Larry McVoy
2007-10-02 20:40 ` Rick Jones
2007-10-02 20:42 ` Wayne Scott
2007-10-02 21:56 ` Linus Torvalds
2007-10-02 19:27 ` Linus Torvalds
2007-10-02 19:53 ` Rick Jones
2007-10-02 20:33 ` David Miller
2007-10-02 20:44 ` Roland Dreier
2007-10-02 21:21 ` Larry McVoy
2007-10-03 21:13 ` Pekka Pietikainen
2007-10-03 21:23 ` Larry McVoy
2007-10-03 21:50 ` Pekka Pietikainen
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=20071003031906.5f0d7cfd.billfink@mindspring.com \
--to=billfink@mindspring$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=lm@bitmover$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=rick.jones2@hp$(echo .)com \
--cc=torvalds@linux-foundation$(echo .)org \
--cc=wscott@bitmover$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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