SAN JOSE, Calif. Sun Microsystems announced Neptune, a 10 Gbit/second Ethernet card and chip optimized for use with multi-threaded processors such as Sun's Niagara. Rather than use the specialized hardware called TCP offload engines (TOEs) favored by many network companies, Sun's chip classifies and assigns traffic flows to as many as 24 threads in a server.
Like Intel, Sun is taking an approach that uses its microprocessors to handle the growing processing requirements of Ethernet. In fact, a slightly simplified version of the 90nm Neptune core now shipping on a Sun adapter card will appear as a block in the 65nm Niagara2 processor in development at Sun.
Sun's move further fragments the emerging field of 10 Gbit Ethernet products.
A number of companies including Cisco Systems, Hewlett-Packard and Microsoft worked for several years to establish remote direct memory access approach, typically using dedicated hardware in a media access controller to handle the overhead of 10 Gbit Ethernet. But with Sun and Intel both rolling out their own approaches that rely on unique features in their CPUs, the market for chips using the TOE standards will be significantly reduced.
Sun is also open to licensing Neptune at the card or chip level for to other vendors, though it has not completed any licensing deals.
Sun will offer the Neptune card as an option for all its systems, whether they are based on Niagara or Intel or AMD x86 processors. However, it is not clear how Neptune will work with Intel Xeon processors that use Intel's so-called IOAT approach to accelerating Ethernet traffic by using features on the Intel CPUs and chip sets.
Neptune sports two 10Gbit ports or can be configured to support four Gbit Ethernet links. The ASIC includes a packet classification block that defines and assigns packet flows to dedicated Direct Memory Access (DMA) engines on the chip. It then binds that flow to specific CPUs and threads in a server.
Using this approach with the Sun Solaris operating system, Sun said Neptune will deliver throughput of more than 8 Gbits/second based on small TCP/IP packets. Sun claims throughput of more than 7.5 Gbits/second for small packets running under Linux. Large, so-called jumbo packet frames, typically flow at full 10 Gbit/s line rates.
By contrast, Sun claims, some existing 10G Ethernet cards get throughput of as little as 3-4 Gbits/s on the kinds of small packet flows typical of Web servers.
"Most people can get full line speed when they use large jumbo frames," said Dilip Modi, a product architect in Sun's networking group. "We are trying to establish ourselves as the leaders in 10G Ethernet in the server," he added.
Inside Neptune, Sun has built 40 dedicated hardware DMA blocks, 24 for transmitting and 16 for receiving data. The chip also has un undisclosed amount of supporting buffers and interrupts to handle breaking its 20 Gbit/s total throughput into as many as 24 separate flows, each dedicated to a specific CPU and thread.
"We do parallelism right from the start as data packets come into your system," Modi said. "Data goes directly to a DMA engine rather than to a common domain zero pool," he added.
Sun is updating Solaris, putting pieces of a new virtualization architecture in place over the course of the year. New features include the ability for a network card to bind packet flows to a particular CPU and thread.
The Sun card uses an 8x PCI Express link and consumes an average of 20W and a maximum of 24W. The version going into the Niagara2 CPU will have the Express link and optional 4x Gbit configuration capabilities stripped out.
The card is available with XFP optical transceivers supporting short or long range distances. Sun aims to demonstrate at Interop later this year a version supporting 10GBase-T copper links using physical layer chips from either Solarflare or Terranetics. That card will ship at the end of the year.
The card will cost about $1,600 outfitted with short-range optics or $1,900 with the long-range transceivers. Sun said that compares to about $500 for today's Gbit Ethernet cards for optical links.