Xen users - Sep 2012 - Issue with domU RX throughput

Hi,

I am encountering a weird issue, where domU RX throughput (of traffic from
another machine) is very low. But domU RX throughput from dom0 is fine,
and dom0 RX from another machine is fine. iperf reported the following
throughputs:

dom0 <- outside -- 942Mbps
domU <- dom0 -- 3467Mbps
domU <- outside -- 87Mbps

The NIC on the machine is 1GE.

What puzzles me is, some instances of domU (with same config) is able to
achieve almost 1Gbps RX throughput. And this seem to be very random.

I am running Debian stable (Squeeze) with standard Xen packages,
and standard network setup with linux bridging module. NIC is Broadcomm
BCM5764M GE.

Please let me know, if more information on configuration/tests is required.

Thanks,
Shoban

Nevermind. The issue seemed to be with the switch, and its
flow-control mechanism.

Thanks,
Shoban

On Mon, Sep 10, 2012 at 5:36 PM, Shoban <shoban.preeth@gmail.com>
wrote:
> Hi,
>
> I am encountering a weird issue, where domU RX throughput (of traffic from
> another machine) is very low. But domU RX throughput from dom0 is fine,
> and dom0 RX from another machine is fine. iperf reported the following
> throughputs:
>
> dom0 <- outside -- 942Mbps
> domU <- dom0 -- 3467Mbps
> domU <- outside -- 87Mbps
>
> The NIC on the machine is 1GE.
>
> What puzzles me is, some instances of domU (with same config) is able to
> achieve almost 1Gbps RX throughput. And this seem to be very random.
>
> I am running Debian stable (Squeeze) with standard Xen packages,
> and standard network setup with linux bridging module. NIC is Broadcomm
> BCM5764M GE.
>
> Please let me know, if more information on configuration/tests is required.
>
> Thanks,
> Shoban