We are running a number of Debian Wheezy VMs on top of Ubuntu Servers 12.04.4 / Libvirt 0.9.8-2ubuntu17.17
The host is connected to the network through a trunk. It then split the VLANs and create a bridge for each of them with the following conf:
auto eth4.2 kvmbrtrunk.2 iface eth4.2 inet manual up ifconfig eth4.2 up down ifconfig eth4.2 down iface kvmbrtrunk.2 inet manual bridge-ports eth4.2 bridge-stp no bridge-fd 0 bridge-maxwait 0
The VMs are configured as follow:
<interface type='bridge'> <mac address='54:52:00:02:10:70'/> <source bridge='kvmbrtrunk.2'/> <model type='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/> </interface>
And they use VirtIO
00:09.0 Ethernet controller: Red Hat, Inc Virtio network device
Protagonists (all on same VLAN):
A: 1st Ubuntu 12.04 desktop B: 2nd Ubuntu 12.04 desktop C: 1st VM, 1st host D: 2nd VM, 1st host E: 3rd VM, 2nd host
When we do a serie of 60 pings "rtt min/avg/max/mdev":
A -> B = 0.093/0.132/0.158/0.015 ms A -> C = 0.272/0.434/1.074/0.113 ms A -> D = 0.294/0.460/0.832/0.091 ms A -> E = 0.324/0.505/0.831/0.069 ms C -> D = 0.348/0.607/0.863/0.124 ms C -> E = 0.541/0.792/0.972/0.101 ms
So those results seem to indicate that the libvirt's virtual switch/filtering not only adds some latency, as one might expect, but triples it (0.132 vs 0.460)
Is there anything that can be done to attenuate this extra latency?
Thanks in advance for any tips.