New Intel Xeon 5500 “Nehalem” CPUs are starting to ship
In our industry, new CPU announcements are a dime a dozen. Most of them are simple speed bumps, or at the most an increase in the number of cores per socket.
The Nehalem announcement was different, in that Intel was solving the bus limits that have impacted overall system throughput. The announcement was exciting but being able to buy systems containing those CPUs took a long time to reach fruition. Pre-release performance tests of these new Xeon 5500 CPUs revealed that the announcement was more than marketing. They show that Nehalem provides breakthrough increases in many aspects of system throughput. In many areas, the 5500 is twice as fast as its predecessor 5400. Unfortunately the 5500 is not a drop-in replacement for other Xeon CPUs. It requires a new chip set and socket.
The enhanced feature set and performance are going to make it worth the effort to roll out new systems and motherboards. The first shipping CPUs are quad-core. Memory I/O is now up to 3X faster. The CPUs are more “green” in that they detect how much work is being requested and power-down unused components. They can also increase performance in a given core if other cores are not needed. Especially exciting for virtualization users is that the hardware provides more virtualization assistance in the form of Intel VT-c. I/O and paging in virtual environments should be faster as virtual machines no longer need the host OS to do page table lookups for them.
As of today, Intel is shipping those CPUs. Specifically they are shipping 1 and 2 socket EP versions. Apple has previously announced Nehalem-based workstations, but today many vendors announced servers. The 4-socket EX servers are expected later this year and will lead to another round of price / performance / feature-set / density leading servers.
eWeek.com has a good summary of the CPU architecture and its benefits. The Intel web site includes whitepapers and videos about the Nehalem architecture. ars technica provides a good CPU overview as well as a detailed review of the single-socket Nehalem. Real World Technologies wrote an article describing all the gory technical details of Nehalem.
