VM to VM gigabit communication limits

[pgis]

When you communicate between two VMs that are on the same network bridge does the traffic make it down to the physical layer? (Is the VM to VM network limited to the speed of the bridge its tied to?)

 

[spirit]

When you communicate between two VMs that are on the same network bridge does the traffic make it down to the physical layer? (Is the VM to VM network limited to the speed of the bridge its tied to?)

between 2 vms on the same vmbr, the traffic is internal only and not going out to your physical switches

 

[Dunuin]

Like spirit already said, if both are on the same bridge you are not limited by the Gbit NIC. Whats possible depends on how fast your CPU can handle the packets. Here I get around 3-5 Gbit.

 

[spirit]

Like spirit already said, if both are on the same bridge you are not limited by the Gbit NIC. Whats possible depends on how fast your CPU can handle the packets. Here I get around 3-5 Gbit.

yep, it's more a packet per second limit related to cpu power. (with big packets, you can reach easily 20gbits)

 

[pgis]

thanks for confirming, gonna hafta figure out why I'm only seeing a lil less that 1G speeds between vms... I'll look into packet size...

 

[Dunuin]

Did you choose virtio as your virtual NIC? E1000 and so on aren't that fast.

 

[pgis]

Did you choose virtio as your virtual NIC? E1000 and so on aren't that fast.

thanks for the tip! I actually have one virtio and one e1000 on that vm and I dont recall which one the test was over.... I'm going to rerun it.

edit: yea that made a significant difference, seeing speeds I expected now