Intel and AMD show divergent multi-core strategies

IBM's ex5 supports Intel's Xeon 7500 with up to 3TB of memory

Intel and AMD unveiled new multi-core processor chips this week that push the number of onboard cores to eight or more, allowing system vendors to cram even more performance into servers and workstations.

While the new Opteron and Xeon families are likely to benefit applications such as databases and virtualisation, which require huge amounts of memory and the ability to handle multiple threads, the two firms appear to be aiming at different markets.

Intel is targeting its chips at the largest mission-critical enterprise servers, while AMD has the mainstream market and high-density server environment in its sights.

Intel's Xeon 7500 series processors have up to eight cores and are designed for systems with two, four or eight processor sockets. The top-end Xeon X7560 chip can thus fit out a server with up to 64 processor cores. Each chip can also control up to 16 DIMM slots for memory modules, which allows for up to 1TB of memory in a four-socket system, or up to 2TB for eight sockets.

However, Intel is putting as much emphasis on new reliability, availability and serviceability features as on the raw processing power of the new Xeons, including the Machine Check Architecture technology from Intel's Itanium processor family, which detects and corrects for hardware errors such as memory corruption. The Xeon 7500 series are the first x86 chips to include such features.

Kirk Skaugen, vice president of Intel's architecture group, said that the Xeon 7500 "brings mission-critical capabilities to the mainstream by delivering the most significant leap in performance, scalability and reliability ever seen from Intel".

Vendors backing Intel's platform have in several cases extended its capabilities to support more processors and even larger memory capacities. IBM's ex5 portfolio, announced earlier in March, can be configured with up to 3TB of memory through a plug-in memory module, for example.

At the extreme end of the scale is SGI's Altix UV series, built around custom node controller chips that can support a large number of processor sockets. Altix models include the UV 100, which scales to 96 sockets and 6TB of shared memory in a 3U rack-mount enclosure, while the UV 1000 ships as an integrated cabinet supporting up to 256 sockets (2,048 cores) and 16TB of shared memory, offering up to 18.5 teraflops in performance.

This means that the Xeon 7500 is moving into the space already occupied by Intel's Itanium family of processors, and may mark the beginning of the end for this much maligned architecture, according to Gordon Haff, principal IT advisor at analyst firm llluminata.

"Intel has decided to pull out all the stops on Xeon rather than continuing to position Itanium as the chip for the most mission-critical environments. It remains committed to Itanium, but its positioning relative to Xeon is based on operating system more than inherent chip capability," he said.