Virtualization: The Swiss Army knife of networking?

Startup Neterion Inc. has rolled out a chip that lets systems split one 10GbE link into as many as 16 virtual connections. The effort marks the latest milestone in a long quest to deliver a Swiss Army knife of networking capabilities for the data center in a single slice of silicon.

Virtualization is seen as the next hot feature for the servers that drive the Internet and back-end business computing. Ultimately, server makers hope to meld the technology with many others in chips that handle a combination of networking, storage and clustering jobs.

That goal is probably still more than a year away. In part, that's because the feature requirements list keeps growing, forcing respins of the chips along with sometimes-Herculean software-development efforts for devices that serve today's tiny market, albeit one with huge potential.

Chosen few
Neterion is one of the few companies competing to be the first to deliver all those features on advanced forms of Ethernet. The group faces competition from Mellanox Technologies, which is in the final stages of testing and writing software for 40Gbit/s Infiniband switch and adapter chips. Versions that will handle Ethernet and Fibre Channel are expected to ship in 2H.

Neterion's X3100 series chips carve parallel, bi-directional paths in silicon to let 16 independent jobs use a single 10GbE link simultaneously. It implements the new single-root I/O virtualization (SR-IOV) standards from the PCI Special Interest Group and proprietary techniques found in the latest software from virtualization specialist VMware Inc.

"This is a cost and a performance breakthrough, because the dirty little secret of virtualization is that as you start piling apps on a server, you can bring it to its knees," said Neterion CEO Dave Zabrowski.

The startup says its chip delivers throughput of 16Gbit/s across its two 10GbE links, even under heavy virtualization loads, compared with 2G-4Gbit/s for some competing chips. The device, which dissipates 12W on average, is tailored for servers using as many as four quad-core processors. It was scheduled to get to production this month at an undisclosed cost.

Neterion recently became the first chipmaker to support the NetQueue techniques VMware baked into its ESX version 3.5, released last December. The chip also moves from PCI-X to the 2.5GHz version of PCIe. The startup has gotten an edge in virtualization in part because of its longstanding work with IBM and Hewlett-Packard on proprietary Unix systems. "They are ahead of everyone else in virtualization, and getting there early, they could become a de facto standard," said Bob Wheeler, an analyst with The Linley Group.

The VMware software could be an early driver for 10GbE deployments, Wheeler said, since its queuing technique helps 10Gbit devices achieve something closer to their full throughput when running the virtualization software that OEMs and end users want to get the most bang for the buck from servers.

Becoming more attractive
"Virtualization has the potential to drive 10GbE adoption, but until now the products haven't had good enough performance," Wheeler said. With the ESX 3.5 software, "now the technology becomes attractive for high-end servers," he added.

Designers of virtualization software say they will support the new PCI hardware standard, but in some respects, it represents a step backward. "Hardware vendors tend to spin this as a panacea, but it is not," said Simon Crosby, group chief technologist at Citrix Systems.

The PCI SR-IOV spec "breaks the model of having guest software that runs independently of hardware, and makes the software need to think about hardware dependencies again," Crosby said. "In general, we see significant improvement [with PCI IOV] in workloads where you are really hammering the system with virtualization."

But developers are still working through concerns about reliability with sampling hardware and beta code, said Crosby.

"This won't be in volume hardware until sometime next year, and it is not clear exactly what it means to end users yet," he said.

The trouble is that chipmakers implement the PCI spec in unique ways, forcing software to follow the particularities in the chips' software drivers. Problems arise when a virtual session on one chip fails and has to shift to a session on another chip that may have a slightly different feature set.




Virtualization is on the rise. Real servers will take on more virtual jobs to improve system utilization.


Puzzle pieces
Virtualization is just the latest in a laundry list of advanced networking features designers are trying to pack into Ethernet in hopes of creating a unified data center fabric for servers, switches and storage arrays.

Like Neterion, startups NetXen and ServerEngines are prepping 10GbE silicon supporting the latest PCIe links and virtualization standards. Each device has its own mix of features that capture a snapshot in time of where the industry is driving the technology.

Thus far, no one has gotten all the pieces of the puzzle together yet," said analyst Wheeler.

Just beginning
"I don't know if we will get to one chip with everything in it, but to flesh out this converged-fabric concept, you need to get as much capability out there as possible, and we are still early in this effort," said Michael Krause, an interconnect specialist in the PC server group at Hewlett-Packard Co. "It's a longer period of time before you get all this in the chips in a way that's cost- and power-efficient."

In the meantime, 10GbE products of all sorts have been relatively expensive and slow. That translated into sales of just 50,000 such products last year, according to Linley Group estimates, penetrating a tiny fraction of a market of more than 10 million servers sold annually.

ServerEngines this month hopes to sample a new version of the 10GbE chip it announced in July. The device will step from 2.5GHz to 5GHz PCIe links and will support the SR-IOV specification.

The follow-on PCIe standard, called multiroot IOV, should be completed officially this month. The spec enables jobs from more than one server to share I/O resources.

The total throughput of ServerEngines' dual-ported chip will rise from about 13Gbit/s to full-rated speeds closer to 20Gbit/s, thanks to the 5GHz PCIe links. "People are dead if they don't have that," said Kim Brown, VP of business development for the startup.




Neterion's the big fish in tiny 10G Ethernet pond. Just 50k cards shipped in '07 market of 10 million+ servers.


ServerEngines has drivers for the VMWare ESX 3.5 software in certification now. Whereas its current, 130nm chip supports 32 separate protected domains to handle virtualization, the next-generation, 90nm part increases that to 64 domains.

For its part, NetXen expects to wait until later this year to roll out a chip supporting 5GHz Express. That's when Intel Corp. is expected to launch its first server chip sets supporting the link as part of its 45nm Nehalem family of processors.

NetXen says it gets one-way throughput of about 9Gbit/s per 10GbE port under the latest VMware software, although CPU utilization levels have gone up. The drain on host processors will ease when support for the SR-IOV standard kicks in toward the end of the year, said David Pulling, NetXen president.

- Rick Merritt
EE Times