Funnily enough, the week turned out to be so busy that I never got around to talking about AMD’s Opteron 6000 series. The main changes vs. the previous high-end Opterons are:
- Twice as many cores: The 6000 family tops out at 12 cores/socket, a feat achieved by taking two 6-core modules and putting them on the same chip.
- Memory: The two channel DDR2 memory controller is replaced by a four channel DDR3 memory controller to improve both memory capacity (12 DIMMS/CPU) and memory throughput.
- 2- and 4-socket support: Vendors can build both 2- and 4-socket servers using the Opteron 6000 family.
- No 8-socket support: Anybody waiting for 8-socket Opteron 6000 server should prepare for a disappointment. Existing users of 8-socket Opteron servers will have to turn to Intel if they need 8-sockets in the future.
- Direct Connect 2.0: Previous generations of 4-socket AMD-based servers had the sockets connected to each other in a ring configuration, so that accessing memory attached to another socket might involve two hops. The new architecture connects the sockets in a mesh, with each socket connected directly to the other 3 sockets. The net result is reduced memory latency for access to memory attached to another socket.
All this adds up to a rather different view of the how the commodity server market will develop. AMD is putting it’s faith in sweet spot of the market, large 2-socket servers and cheaper 4-socket configurations, with an emphasis on power efficiency. Given AMD’s desire to get a larger percentage of the commodity server market this makes a lot of sense, A few extra percentage points of market share in the 2-socket market will do much more good for their bottom-line than complete ownership of the 8-socket and above market.
The wisdom of AMD’s decision to cede the 8-socket and above market to Intel’s Xeon 7500 series remains to be seen. On the one hand, historically this market has been tiny, for several reasons:
- Reliability: The market for applications that require large servers has always required high levels of reliability as well. Put simply, any application that demands tens of processors and terabytes of memory is almost by definition “mission critical” since it usually serves an important function in the IT infrastructure.
- Cost: Systems that have offered 8 or more sockets have required specialist chipsets to deliver the required scalability and availability. As soon as you start needing proprietary chipsets, the cost goes up dramatically.
- Scale out: Many applications that used to require large socket-count systems have been redesigned to scale out across many smaller servers.
On the other hand, Intel’s Xeon 7500 removes at least two of the reasons, reliability and cost, by borrowing the reliability features of Itanium and enabling OEMs to build “cookie-cutter” 8-socket configurations that can support 1TB of memory with 8GB DIMMs.
Footnote: At launch, AMD didn’t offer any VMmark numbers, leaving that job to their OEMs who will no doubt have something to say on the matter when they officially launch their AMD-based offerings later this quarter.
Posted by: Nik Simpson