Can you repeat these tests with NAPI and no binding and see if you get any
reordering?
cheers,
jamal
On Tue, 8 Oct 2002, Xiaoliang (David) Wei wrote:
> Thank you Ben.
> I did some UDP test with Iperf. Here are the results:
> Without bounding CPU, I had thousands of pakcets out of order in
> 1.7GByte* 2 connection transmission, with standard MTU. The throughput is
> about 550Mbps*2 (connection) with UDP packets. The sender can send 800Mbps
> for each connection.
> With CPU bounding, I had no packet out of order. Anyway, the two
> connections got only 1.3~1.4 throughput totally. The senders seemed to be
> able to send 1.6Gbps totally. (So, it seems that receiving packets takes
> more time than sending packets)
> Anyway, for a single connection on these machines, I could get 950Mbps.
> Is there any suggestion to improve the Dual CPU-Dual NIC performance? I
> looked at the "top". The two Iperf processes seemed to be using more than
> 60% CPU each. That means they are using different CPU. Anyway, I am not sure
> if they migrated from one CPU to the other very often or not. If they
> changed very often, it may resulted in the low performance, I guess. Is
> there anyway to bound a process to a specific CPU?
> The machines are with Dual Xeon 2.2 G CPU and Dual SysKonnect
> Gigabit-Ethernet Card. All the tests were done with UDP. (Iperf -s -u /
> Iperf -c -u -b1.7G.)
> Thanks.
>
> -David
> Xiaoliang (David) Wei Graduate Student in CS@Caltech
> http://www.cs.caltech.edu/~weixl
> ====================================================
> ----- Original Message -----
> From: "Ben Greear" <greearb@xxxxxxxxxxxxxxx>
> To: "Xiaoliang (David) Wei" <weixl@xxxxxxxxxxx>
> Cc: <netdev@xxxxxxxxxxx>
> Sent: Monday, October 07, 2002 11:24 AM
> Subject: Re: How can we bound one CPU to one Gigabit NIC?
>
>
> > Xiaoliang (David) Wei wrote:
> > > Hi Everyone,
> > > I am now doing some experiments on Dual CPU (2.4Ghz) with 2
> Gigabit
> > > cards. Can anyone tell me how to bound one CPU to each NIC so that we
> don't
> > > need to care about the packet-reordering and the interrupt sharing
> problems?
> > > Thank you very much.:)
> >
> > My experiments show you will still get re-ordered packets occasionally
> > (but then again, I'm having other wierd problems, so maybe you wont).
> >
> > # Bind processor 2 (1<<1) to irq 11
> > echo 2 > /proc/irq/11/smp_affinity
> >
> > # Bind processor 1 (1<<0) to irq 19
> > echo 1 > /proc/irq/9/smp_affinity
> >
> >
> > I will be interested to hear of your results, as I have been having
> > heating problems with e1000 and other problems with tg3 based nics!
> >
> > Ben
> >
> > >
> > >
> > >
> > > Xiaoliang (David) Wei Graduate Student in CS@Caltech
> > > http://www.cs.caltech.edu/~weixl
> > > ====================================================
> > >
> >
> >
> > --
> > Ben Greear <greearb@xxxxxxxxxxxxxxx> <Ben_Greear AT excite.com>
> > President of Candela Technologies Inc http://www.candelatech.com
> > ScryMUD: http://scry.wanfear.com http://scry.wanfear.com/~greear
> >
> >
> >
> >
>
>
>
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