[FreeBSD 8.2 amd64 XENHVM] DomU terrible network performance trought NAT

[Tobias P. Santos]

laurent.cligny at gmail.com wrote:
> Le 12/05/2011 17:02, Tobias P. Santos a écrit :
>   
>> Try this:
>>
>> ifconfig xn1 -txcsum
>>
>> Best regards,
>> Tobias.
>>     
> Hello Tobias,
>
> Unfortunately ifconfig xn1 -txcsum didn't give me lot of result.
> Doing this my network perf through NAT is about 7KiB/s (that is better
> than before, but still unworkable).
>
> Thanks for the idea, maybe we are not that far away from the solution.
>
>   
We had a problem where traffic between VMs was too slow (about 5Mbps on 
a Gigabit network) and disabling TX checksum solved the problem 
(actually, speed increased to more than 1Gbps).
Your problem is different as you have a nice throughput between VMs on 
xn1, sorry that I missed that on my first message.

Did you try to transfer data from something connected to xn0 to one of 
yours DomU servers connected to xn1 without NAT?
You also mentioned pf. Did you make any test using natd or anything else?
Something tells me that's not a nic problem, but that's just a guess.

Anyway, on the coming weeks I will have to set up a similar environment 
to yours, so maybe I'll face the same problem (although we use natd 
daemon instead of pf).

Good luck!