Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 1 Sep 2012 00:26:55 +0200
From:      =?ISO-8859-1?Q?Olivier_Cochard=2DLabb=E9?= <olivier@cochard.me>
To:        Norbert Aschendorff <norbert.aschendorff@yahoo.de>
Cc:        freebsd-stable@freebsd.org
Subject:   Re: IPv4 vs. IPv6 Ethernet Performance
Message-ID:  <CA%2Bq%2BTcopbjXFMwEY2Y5F3xZDs8poTAWVSKFexgWp-MjvTFoV2A@mail.gmail.com>
In-Reply-To: <503F8186.4070906@yahoo.de>
References:  <503CE60F.8040007@yahoo.de> <loom.20120829T133814-120@post.gmane.org> <503E5C14.9090001@yahoo.de> <CA%2Bq%2BTcpkgecViB%2B9ze=UX7=UYq1YKkN690X6XAzYcpcrdZtO2w@mail.gmail.com> <503F8186.4070906@yahoo.de>

next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Aug 30, 2012 at 5:06 PM, Norbert Aschendorff
<norbert.aschendorff@yahoo.de> wrote:
> I tested it using tcpdump: http://nopaste.info/9394068f54_nl.html
> The length field says for each packet 1408 bytes, so that should be OK.
>

TCP the packet size is OK (MSS negociated), it's in IPv6 UDP mode that
iperf have a problem with the default packet size:

"iperf -V -u -c desthost"

"tcpdump host desthost" output  (notice the frag and default length):

00:08:33.256304 IP6 (flowlabel 0x09036, hlim 64, next-header Fragment
(44) payload length: 1440) 2001:db8::1 > 2001:db8::2: frag
(0x3c8d768a:0|1432) 39065 > commplex-link: UDP, length 1470
00:08:33.256307 IP6 (flowlabel 0x09036, hlim 64, next-header Fragment
(44) payload length: 54) 2001:db8::1 > 2001:db8::2: frag
(0x3c8d768a:1432|46)
00:08:33.256317 IP6 (flowlabel 0x09036, hlim 64, next-header Fragment
(44) payload length: 1440) 2001:db8::1 > 2001:db8::2: frag
(0x6f6f083c:0|1432) 39065 > commplex-link: UDP, length 1470
00:08:33.256320 IP6 (flowlabel 0x09036, hlim 64, next-header Fragment
(44) payload length: 54) 2001:db8::1 > 2001:db8::1: frag
(0x6f6f083c:1432|46)

Regards,

olivier



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CA%2Bq%2BTcopbjXFMwEY2Y5F3xZDs8poTAWVSKFexgWp-MjvTFoV2A>