VirtualBox Linux Host & Guests

[Daniel L. Miller]

Not directly on topic - but since I think there are people here who use 
VirtualBox with Nginx I'll ask.  At first I thought I had nginx 
configuration problems - but even if I do, I know my core issue is 
VirtualBox/Linux networking.

I have a Linux host (AMD Opteron, 6-core, 16GB) with multiple VirtualBox 
VM's.  After tests and experiments, I'm now using the Intel T Server 
network interface for the guests (I WAS using the virtio - but 
performance was horrible).  The guests are bridged. I'm using Ubuntu 
"Precise" for both host & guests and "Guest Extensions" is installed on 
all guests.

My first question - is anyone using the virtio interface successfully?  
And measured your performance to know it's working?

But the real question - what if any adjustments have you made, either to 
VirtualBox or to Linux, to achieve optimum network performance?  Having 
switched to the Intel interface my Linux guests have gotten much better 
- but still not where I think they should be (which to me means the 
virtualization should be transparent - guests should have the same speed 
as the host).  I have Windows guests that are working perfectly - it's 
only the Linux guests that have issues.

-- 
Daniel