A problem on TCP in High RTT Environment.

[Niu Zhixiong]

For 60s test at 20Mbps, 200ms delay
with hw.igb.num_queues=2
speed is 9.5Mbps.
and without it
the speed is 9.1Mbps.

However, SCTP is 17.10.

For 60s test at 20Mbps, 150ms delay
with hw.igb.num_queues=2
speed is 11.1Mbps.
and without it
the speed is 9.92Mbps.
However, SCTP is 18.59.

For 60s test at 20Mbps, 150ms delay
with hw.igb.num_queues=2
speed is 11.13Mbps.
and without it
the speed is 9.92Mbps.
However, SCTP is 18.59.

For 60s test at 20Mbps, 100ms delay
with hw.igb.num_queues=2
speed is 9.9Mbps.
and without it
the speed is 11.13Mbps.


For 60s test at 20Mbps, 50ms delay
with hw.igb.num_queues=2
speed is 13.1Mbps.
and without it
the speed is 13.1Mbps.

For 60s test at 20Mbps, 10ms delay
with hw.igb.num_queues=2
speed is 18.0619Mbps.
and without it
the speed is 18.12Mbps.


Regards,
Niu Zhixiong
－－－－－－－－－－－－－－－
 kaiaixi at gmail.com


On Mon, Aug 11, 2014 at 7:50 PM, Michael Tuexen <
Michael.Tuexen at lurchi.franken.de> wrote:

> On 11 Aug 2014, at 09:32, Niu Zhixiong <kaiaixi at gmail.com> wrote:
>
> > Thanks for your reminding. I tried hw.igb.num_queues=2 just now. But,
> the throughput is still slow. And When I tested same things in my Virtual
> machine-based environment(use Virtio), the throughput is similar(SCTP is 2x
> than TCP).
> So is the curve still the same or is it now constantly half of the SCTP
> throughput which
> was almost constant for different RTTs...
>
> Best regards
> Michael
> >
> > Regards,
> > Niu Zhixiong
> > －－－－－－－－－－－－－－－
> >  kaiaixi at gmail.com
> >
> >
> > On Mon, Aug 11, 2014 at 3:08 PM, Eggert, Lars <lars at netapp.com> wrote:
> > Hi,
> >
> > On 2014-8-10, at 5:48, Niu Zhixiong <kaiaixi at gmail.com> wrote:
> > > I am using Intel I350-T4 NIC.
> >
> > igb driver?
> >
> > I've been having weird issues with this driver under 10-RELEASE, too. On
> one machine, I had to limit hw.igb.num_queues=2 in order to get any sort of
> useful connectivity. On another machine, I had to severely bump
> kern.ipc.nmbclusters & friends. I'm not sure this is the issue here, since
> SCTP seems to be working OK, but I'm not trusting igb NICs at the moment.
> >
> > Lars
> >
>
>