A lot has been written about the coming age of I/O virtualization and the rise of integrated fabrics, driven largely by new switching platforms by Cisco, Brocade and others. While these systems are certainly on the cutting edge of enterprise network technology, the fact is that an even more significant revolution is taking place on the processor level.
In the past few weeks, we've seen a number of developments from the likes of Neterion and ServerEngines based on the new single-root I/O virtualization (SR-IOV) standard from the PCI-SIG. But any examination of silicon-level I/O virtualization wouldn't be complete without a peek into what Intel has been up to.
The latest news is that the company is implementing its Virtual Machine Device Queues (VMDq) technology on both the chip level and in its latest NIC cards. Essentially, this is a switch offload technique that draws many of the switching functions out of the virtual machine onto specialized hardware. This frees up overhead in the VM, allowing it to perform application-related tasks much more efficiently.
VMDq is likely to show up first in VMware environments. At VMworld this week, Intel showed how the technology can be used with the NetQueue system in the ESX platform to better align packet queues in 10 GbE networks. The demo showed throughput on an eight-way host with eight VMs jumping from 4 Gbps to more than 9 Gbps with VMDq.
VMDq is only one part of Intel's overall virtual I/O strategy, dubbed VT-d (Virtualization Technology for Directed I/O). The full platform includes advances in VM monitoring, DMA remapping and resource assignment and sharing. Although somewhat dated, the best overview of the VT-d platform is on Intel's site. It looks like Parallels is taking the lead in implementing VT-d, coming out with "experimental support" on the Beta 2 version of the new Parallels Server system.
Whether you're talking about VMware, Xen, Hyper-V or any other virtualization system out there, they all rely on the host CPU to work their magic. But there is an awful lot of housekeeping going on to ensure those systems function properly over the network. With more of those mundane tasks shifting over to hardware or down to the silicon itself, going virtual will only get easier and cheaper as time goes on.