Sun Microsystems claimed a new watermark for server CPUs at the Hot Chips conference with its 16-core, 128-thread Rainbow Falls processor. Analysts, however, gave the IBM Power7 kudos as the more compelling achievement in the latest round of high-end server processors.
Power7 packs as many as 32 cores supporting 128 threads on a four-chip module with links to handle up to 32 sockets in a system. “It is scaling well beyond anything we’ve ever really seen before,” said Peter Glaskowsky, a technology analyst for Envisioneering Group.
Power7 includes 32Mbytes in embedded DRAM in L3 cache alone. The chip also sports 590GBps total chip bandwidth including two four-channel memory controllers per die. By contrast, Sun’s design—focused on raw thread throughput for Web servers—does not even use a level three cache. However, Sun is expected to adopt L3 cache in future chips.
