On Fri, Apr 24, 2015 at 1:17 PM, Luke Gorrie <luke@xxxxxxxx> wrote: > On 24 April 2015 at 11:47, Stefan Hajnoczi <stefanha@xxxxxxxxx> wrote: >> >> My concern is the overhead of the vhost_net component copying >> descriptors between NICs. > > > I see. So you would not have to reserve CPU resources for vswitches. Instead > you would give all cores to the VMs and they would pay for their own > networking. This would be especially appealing in the extreme case where all > networking is "Layer 1" connectivity between local virtual machines. > > This would make VM<->VM links different to VM<->network links. I suppose > that when you created VMs you would need to be conscious of whether or not > you are placing them on the same host or NUMA node so that you can predict > what network performance will be available. The motivation for making VM-to-VM fast is that while software switches on the host are efficient today (thanks to vhost-user), there is no efficient solution if the software switch is a VM. Have you had requests to run SnabbSwitch in a VM instead of on the host? For example, if someone wants to deploy it in a cloud environment they will not be allowed to run arbitrary software on the host. Stefan _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
