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Greetings,

We have deployed Neutron+OVS+GRE for networking.
All work fine except a problem that, when accessing to internet within a 
VM, the speed is really slow. For example, running apt-get is much 
slower than expect.
We have changed the MTU for VM to 1400, and turn off GRO.
Do you have met the same issue? what's the general idea for tuning?

Thanks.