The new Nehalem Xserve is out. We’ve waited a couple of days to digest the information so here it is! The new Xserve is named from the next generation chip it has, which makes it the fastest Xserve Apple has yet to ship (this isn’t to say it’s the fastest Xeon, but it is faster overall by 2x-ish). To quote Apple:
Its single-die, 64-bit architecture makes 8MB of fully shared L3 cache readily available to each of the four processor cores. The result is fast access to cache data, reduced traffic between processors, and greater application performance. Combine that with the other technological advances and you get an Xserve that’s up to 2x faster than the previous generation.
But the processor being twice the speed isn’t the only thing that got a major upgrade. The new Xserve can take up to 12 slots (or 6 slots on a the quad-core) worth of 1066MHz DDR3 ECC SDRAM. The RAM is faster, but the new processor has an integrated memory controller, which reduces the latency between RAM and processor, again increasing speed. Each processor can control 3 banks worth of 1066MHz RAM, removing more bottlenecks from the chip to the I/O hub (which is also faster in the latest model, btw). 
Everyone else has been overclocking for years. Not that it’s overclocking, but close enough: introduce TurboBoost. If the other cores of a chip aren’t doing anything then the Nehalem will allow the CPU to spike up from 2.93GHz to 3.33GHz. So you’re not performing an operation telling the CPU to always run faster (and thus hotter). Instead, you’re telling it that if other cores aren’t needed to wind them down and move the heat over to the one that needs the power.
The New Xserve also has some very nice storage options. While we have been able to install 3 drives in the past, at this point there is a fourth drive option (similar to the original Xsever). Rather than being loaded into the front though, this drive is installed inside the system, and it’s a 128 GB solid state drive (SSD). You can also purchase a RAID5 controller for the Xserve. This seems to indicate that installing the Operating System on the Solid State Drive and placing data, be it mail, files, etc on the RAID5 (which doesn’t require a PCI slot) will be a common architectural choice. The Apple Drive Modules (ADMs) can now go up to 1 terabyte each. These are not interchangeable with older Xserves, and they are SATA. If you want to use SAS with the new Xserve, then Promise will now be handling all SAS drive modules (be it for Vtrak or Xserve) for Apple.
A couple of points about the new Xserve:
- The RAID5 controller: ZFS is more efficient than RAID5. Provided you are using ZFS, you can have more useable disk capacity with equal throughput using ZFS.
- If you’re not into headless serving, the dongle doesn’t come with the server any more (like with MacBooks), so make sure to order it, or just steal the one off your neighbors MacBook.
- Expect it to be a few weeks to ship these things (understandably, it’s a whole new gen of Xserve).
- Because it’s a new generation, your old spare parts kit likely won’t get you far with these things, and don’t expect to be swapping ADMs between the servers either.
- The quad-core is only $500 cheaper than the octa-core… Double the possible memory alone will potentially make the octa-core last a year or more longer than the quad-core as a viable production node…
- The SSD is nice and all, but they crash too. Just because there are no moving parts doesn’t mean that they can die. I’m all for using it as your boot volume, but… Make sure to have a bare metal backup, preferably one that is 1-button restore.
- One of the compelling aspects of this server is the processing per unit of rack density. The power requirements have been lowered, the firepower increased and overall the server is a blazing rocket ship. For the first time in a long time it has a very compelling story in the 1U server space: it’s similarly priced to other 1U systems, can run Windows/Linux and is way sexier than any other rack mount server (I know the data center isn’t supposed to be a fashion show but come on, the only other vendor that even cares about rack chassis looks seems to be Sun, who’s strategy is to make them look a little like a MacPro).
