I am using Intel I350-T4 NIC. The LRO is closed by default. And by the way,
when I am using KVM-based virtual machine(virtio NIC) do the exactly same
test. The results are same.

ifconfig igb0
igb0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
options=403bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,VLAN_HWTSO>
 ether a0:36:9f:38:27:d0
inet 10.0.10.3 netmask 0xffffff00 broadcast 10.0.10.255
inet6 fe80::a236:9fff:fe38:27d0%igb0 prefixlen 64 scopeid 0x1
 nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
media: Ethernet autoselect (1000baseT <full-duplex>)
 status: active

Regards,
Niu Zhixiong
---------------
 kaia...@gmail.com


On Sun, Aug 10, 2014 at 11:32 AM, John-Mark Gurney <j...@funkthat.com> wrote:

> Niu Zhixiong wrote this message on Sun, Aug 10, 2014 at 10:50 +0800:
> > I am sorry that I upload a WRONG SCTP capture. But, the throughput is
> same.
> > SCTP is double than TCP, about 18Mbps.
> > ???
> >  sctp_2.pcapng.gz
> > <
> https://docs.google.com/file/d/0By8sTL79ob4tMlh4WDlTSndHX0k/edit?usp=drive_web
> >
> > ???
>
> Ok, the owin graph is very interesting...  We do have a full 2MB window
> on the receiver side, but for some reason, we only ever have just under
> 6k outstanding on the connection...
>
> So, it looks like we send for a short period of time, and then stop
> sending...  Do you have LRO enabled?  I think it might be related to:
> https://svnweb.freebsd.org/changeset/base/r256920
>
> As I'm seeing >100ms gaps where the sender doesn't send any data, and
> as soon as more than one ack comes in, the next segment goes out...  If
> we only receive a single ack, then we wait for a timeout before sending
> the next segment..
>
> Can you try to disable LRO on the receiving host?
>
> ifconfig <iface> -lro
>
> And see if that helps... If it does...  Applying the patch, or compiling
> a more recent kernel from stable/10 that is after r257367 as that is was
> the date that the change was merged...
>
> > On Sun, Aug 10, 2014 at 10:42 AM, Niu Zhixiong <kaia...@gmail.com>
> wrote:
> >
> > > I am sure that wnd is about 2MB all the time.
> > > This is my latest capture, plz see Google Drive.
> > > In the latest test, TCP(0s-120s) is about 9Mbps and SCTP(0s-120s) is
> about
> > > 18Mbps.
> > > (The bandwidth(20Mbps) and delay(200ms) is set by dummynet)
> > > The SCTP and TCP are tested in same environment.
> > >
> > > ???
> > >  sctp.pcapng.gz
> > > <
> https://docs.google.com/file/d/0By8sTL79ob4tYl9sM2V5a19iNVU/edit?usp=drive_web
> >
> > > ??????
> > >  tcp.pcapng.gz
> > > <
> https://docs.google.com/file/d/0By8sTL79ob4tV0NMR1FYLUQ3MWs/edit?usp=drive_web
> >
> > > ???
> > >
> > >
> > >
> > > Regards,
> > > Niu Zhixiong
> > > ?????????????????????????????????????????????
> > >  kaia...@gmail.com
> > >
> > >
> > > On Sun, Aug 10, 2014 at 10:23 AM, John-Mark Gurney <j...@funkthat.com>
> > > wrote:
> > >
> > >> Niu Zhixiong wrote this message on Sun, Aug 10, 2014 at 10:12 +0800:
> > >> > During the TCP4 transmission.
> > >> > Proto Recv-Q Send-Q Local Address          Foreign Address
> > >>  (state)
> > >> > tcp4       0 2097346 10.0.10.2.13504        10.0.10.3.9000
> > >> > ESTABLISHED
> > >>
> > >> Ok, so you are getting a full 2MB in there, and w/ that, you should
> > >> easily be saturating your pipe...
> > >>
> > >> The next thing would be to get a tcpdump, and take a look at the
> > >> window size.. Wireshark has lots of neat tools to make this analysis
> > >> easy...  Another tool that is good is tcptrace..  It can output a
> > >> variety of different graphs that will help you track down, and see
> > >> what part of the system is the problem...
> > >>
> > >> You probably only need a few tens of seconds of the tcpdump...
> > >>
> > >> > On Sun, Aug 10, 2014 at 4:58 AM, Michael Tuexen <
> > >> > michael.tue...@lurchi.franken.de> wrote:
> > >> >
> > >> > >
> > >> > > On 09 Aug 2014, at 22:45, John-Mark Gurney <j...@funkthat.com>
> wrote:
> > >> > >
> > >> > > > Michael Tuexen wrote this message on Sat, Aug 09, 2014 at 21:51
> > >> +0200:
> > >> > > >>
> > >> > > >> On 09 Aug 2014, at 20:42, John-Mark Gurney <j...@funkthat.com>
> > >> wrote:
> > >> > > >>
> > >> > > >>> Niu Zhixiong wrote this message on Fri, Aug 08, 2014 at 20:34
> > >> +0800:
> > >> > > >>>> Dear all,
> > >> > > >>>>
> > >> > > >>>> Last month, I send problems related to FTP/TCP in a high RTT
> > >> > > environment.
> > >> > > >>>> After that, I setup a simulation environment(Dummynet) to
> test
> > >> TCP
> > >> > > and SCTP
> > >> > > >>>> in high delay environment. After finishing the test, I can
> see
> > >> TCP is
> > >> > > >>>> always slower than SCTP. But, I think it is not possible.
> (Plz
> > >> see the
> > >> > > >>>> figure in the attachment). When the delay is 200ms(means
> > >> RTT=400ms).
> > >> > > >>>> Besides, the TCP is extremely slow.
> > >> > > >>>>
> > >> > > >>>> ALL BW=20Mbps, DELAY= 0 ~ 200MS, Packet LOSS = 0 (by
> dummynet)
> > >> > > >>>>
> > >> > > >>>> This is my parameters:
> > >> > > >>>> FreeBSD vfreetest0 10.0-RELEASE FreeBSD 10.0-RELEASE #0: Thu
> Aug
> > >>  7
> > >> > > >>>> 11:04:15 HKT 2014
> > >> > > >>>>
> > >> > > >>>> sysctl net.inet.tcp
> > >> > > >>>
> > >> > > >>> [...]
> > >> > > >>>
> > >> > > >>>> net.inet.tcp.recvbuf_auto: 0
> > >> > > >>>
> > >> > > >>> [...]
> > >> > > >>>
> > >> > > >>>> net.inet.tcp.sendbuf_auto: 0
> > >> > > >>>
> > >> > > >>> Try enabling this...  This should allow the buffer to grow
> large
> > >> enough
> > >> > > >>> to deal w/ the higher latency...
> > >> > > >>>
> > >> > > >>> Also, make sure your program isn't setting the recv buffer
> size
> > >> as that
> > >> > > >>> will disable the auto growing...
> > >> > > >> I think the program sets the buffer to 2MB, which it also does
> for
> > >> SCTP.
> > >> > > >> So having both statically at the same size makes sense for the
> > >> > > comparison.
> > >> > > >> I remember that there was a bug in the combination of LRO and
> > >> delayed
> > >> > > ACK,
> > >> > > >> which was fixed, but I don't remember it was fixed before
> 10.0...
> > >> > > >
> > >> > > > Sounds like disabling LRO and TSO would be a useful test to see
> if
> > >> that
> > >> > > > improves things...  But hiren said that the fix made it, so...
> > >> > > >
> > >> > > >>> If you use netstat -a, you should be able to see the send-q
> on the
> > >> > > >>> sender grow as necessary...
> > >> > > >
> > >> > > > Also, getting the send-q output while it's running would let us
> know
> > >> > > > if the buffer is getting to 2MB or not...
> > >> > > That is correct. Niu: Can you provide this?
>
> --
>   John-Mark Gurney                              Voice: +1 415 225 5579
>
>      "All that I will do, has been done, All that I have, has not."
>
_______________________________________________
freebsd-net@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"

Reply via email to