The network throughput mostly depends on your hardware configuration, instead of cloudstack.
The key components are - Network card : intel ixgbe or broadcom ? - Network device driver version - Network device driver configuration : GRO - using VLAN or not : - using linux bridge or not If you have default configuration with Xenserver 5.6 sp2, the maximum network throughput will be about 2 Gbps. Our experiment shows that - instance to instance : 7Gbps - instance - router vm - instance : 4Gbps with - XenServer 6.0.2 - Custom Intel ixgbe driver - GRO settings - ovs (open vswitch) Cheers, Choonho Son 2012/12/5 Bryan Whitehead <[email protected]> > What is network.throttling.rate and vm.network.throttling.rate set to in > global settings? > > Please correct me if I'm wrong about how these global settings work, but I > think these values override the templates. > > > On Tue, Dec 4, 2012 at 2:58 AM, Wolfram Schlich > <[email protected]>wrote: > > > Hi! > > > > Does a router VM have another kind of network rate > > limitation besides the one from the network offering? > > > > We have the network offering set to 4000 Mbit/s > > which is resembled by XenServer through limiting > > the interface bandwidth to 500MByte/s (checked that). > > > > With unrouted traffic within a CloudStack network > > (between instances running on different nodes that > > all have 10 GbE links), the instances peak at the > > configured 4000 Mbit/s (so, as expected). When > > doing routed traffic between different CloudStack > > networks (passing 2 router VMs), the same test peaks > > at around ~920 Mbit/s while the router VM CPU shows > > to idle about 99% (25k interrupts/s). > > > > The instances used for testing as well as the router > > VMs run on Citrix XenServer 6.0.2 and are all using > > xen_netfront as the virtual ethernet driver (which > > does not even supply a speed value to the VM). > > > > I've also looked for any kind of tc/iptables rules > > on the router VM but couldn't find any that seem > > relevant for this issue. > > > > Ideas, anyone? :-) > > > > Cheers, > > Wolfram > > >
