In-Depth

SGI Unveils 64-way Linux Supercomputers

Altix 3000 systems supports some of the largest Linux SMP configurations to date

• By Stephen Swoyer
• 01/09/2003

Addison Sell, SGI’s product marketing manager for high-performance computing, says his company is currently shipping two Altix 3000-class machines, the Altix 3300 and the Altix 3700. Both systems can be clustered using SGI’s NUMAlink interconnect to support clusters of hundreds of Itanium 2 processors, Sell says. “That’s one instantiation of Linux in 64 processors, so there’s this notion of one node that will have up to [512 GB] of memory. We have…this notion of a supercluster beyond that, where we can connect multiple nodes over our SGI NUMAlink interconnect, scaling to hundreds of processors [right now], thousands next year.”

Sell says that NUMAlink is indifferent to the constraints of memory configurations. If, for example, a job running on a single node requires more memory, it can exploit NUMAlink’s support for Global Shared Memory. “What that means is that processors in any node can directly access the data and memory in other nodes.”

SGI’s Altix 3300 is available in single-node configurations of between four and 12 Itanium 2 processors. The Altix 3700 supports between 16 and 64 chips per node. Both systems enjoy pin compatibility with Intel’s forthcoming Madison and Montecito Itanium processors, which are expected to introduce faster clock speeds and more cache. Madison is due in 2003, while Montecito is expected to ship in 2004.

A Milestone for Linux

According to Nathan Brookwood, a principal with microprocessor research company Insight64, SGI is delivering one of the most scalable Linux-based systems to date. “They’ve got 2 GB/s of actual I/O traffic through Linux, along with very good scalability characteristics, which is something that they’ve had to work on, because Linux by itself doesn’t scale all that well in large SMP configurations.”

Gordon Haff, an analyst with consultancy Illuminata, agrees. “They talk about industry-standard hardware [Itanium 2] and an industry-standard operating system [Linux], but this certainly is not a commodity Linux box. What SGI has done is borrowed heavily from their Origin line [of RISC supercomputers].”

The Altix 3000 line marks SGI’s second foray into Linux-based computing. In 1999, the high-performance computing specialist began shipping a line of Intel-based servers that ran Linux. SGI also introduced a system based on Intel’s first-generation Itanium processor. But while SGI’s first-generation Intel servers were 32-bit machines slated for low-end applications, and its Itanium 1 system was developed for the most part as a prototype, Haff says that the Altix 3000 is the real deal. “What they sort of did in that first round was really Linux as a commodity platform. That really wasn’t terribly successful for them, because…they really weren’t fundamentally bringing any particular value to the table. What they’re doing here is they’re leveraging Linux and Itanium platforms and still adding significant value in terms of their high-end hardware platform.”

Although the Altix 3000 systems borrow heavily from R&D work that SGI originally performed in support of its Origin-based supercomputers, which run the company’s proprietary IRIX operating system, Sell indicates that the Altix 3000 systems run “industry-standard Linux scaling to 64 processors; all you really needed was a better architecture. The modifications that are out there in the open source are the normal sort of chipset support that any vendor would put in.”

No End to IRIX

When SGI first signed on to support Itanium in the late 1990’s, it announced plans to eventually transition existing customers of its MIPS-based IRIX systems on to Itanium. According to Insight64’s Brookwood, however, SGI was forced to abandon that stance in the face of mounting pressure from its IRIX user base. “They discovered that their customers on IRIX weren’t all that enthusiastic about moving over to Linux, so they concluded that if they could keep their IRIX customers happy, they could retain them.”

Consequently, says Sell, SGI will introduce several additional iterations of MIPS and IRIX, along with new Itanium 2 and Linux hardware. “We are continuing forward with the MIPS and IRIX based products. We see those as being very complementary to one another.”

Changing Face of High-Performance Computing

SGI’s new Altix systems are slated for high-performance or technical computing implementations, but Sell says that the term “high-performance computing” today describes a variety of non-traditional applications. “Proctor & Gamble is using our Origin 3900 systems to study the aerodynamics of Pringles chips, because they produce them fast enough so that they have a tendency to become airborne on the conveyor belt. So we’re seeing enterprise customers who want to model their manufacturing processes, for example.”

Sell expects that the price-performance value of Itanium 2 and Linux will create new applications for high-performance computing. He cites data warehousing among other potential uses. “A lot of corporate users don't have big supercomputer installations already and don't want to invest in specialized expertise, but if they already have admins who understand Linux, then that's one way they can invest in this technology.”