10Gig Ethernet specialist Neterion is announcing its third generation of virtualisation-aware network adapters at VMworld Europe this week, with a claim that these NICs will greatly speed up network-intensive tasks such as migrating virtual machines (VMs) from one server to another.
The cards offload work normally done in the hypervisor - in most VMs, the network driver routes I/O to a virtual network within the hypervisor, which then controls the physical network interface.
In contrast, Neterion's X3100 series card behaves like multiple physical network cards, allowing each VM to have its own network interface.
"By offloading many of the hypervisor tasks from host to the X3100 adapters, virtualised applications on VMs can achieve over four times the performance levels of virtualised servers without the offload features," Neterion boss Dave Zabrowski said.
There are other ways to get around the problem of virtualising the network within the hypervisor. One is to allow the VM to cut through to the physical network card, but then the guest OS has to be virtualisation-aware. Or you can simply put in multiple network cards, one per VM - but that breaks the virtual model as your VMs are no longer hardware-independent.
So virtualising network cards from Neterion (and rivals such as Intel, NetXen, NextIO and Solarflare) offload the virtualisation work into hardware. For example, the new Neterion X3100 has 17 hardware-based bidirectional I/O paths, each of which can run at line rate. The idea is that this will match to a 16-core server, with one extra path for management.
The devices are compatible with VMware's ESX Server 3.5 and its NetQueue I/O virtualisation (IOV) spec, and can reduce CPU utilisation by up to 50 per cent via a new Large Receive Offload feature, Zabrowski said.
He claimed they are also the first of their kind to support the PCI-SIG's new SR-IOV (single-root IOV) standard, which allows one adapter to behave like multiple physical adapters in a virtualised server.
"This product is a watershed for the industry," he declared. "With the X3100 series supporting full IOV compliance with a silicon-based I/O path architecture, all applications become candidates to run on a virtualised server."
Dave Malcolm, engineering veep at US-based software developer Surgient, said Neterion's virtualising adapters have enabled his company's ESX 3.5 servers to run at more than 80 per cent utilisation.
"And with the 10Gig line rate performance, we have eliminated the I/O bottlenecks for server-to-server and server-to-storage networking applications," he added. ®