Cray's midrange line big on Xeons, GPUs
Packing some Nehalem-EX punch
In launching the CX1000 midrange supercomputer lineup, it looks like Cray is finally getting tired of trying to peddle Lexuses and BMWs to people who can only afford Fords and Chevys.
As Cray's top brass were hinting it would when it talked about its fourth quarter financial results back in late February, the company has put out a new product that shoots the gap between its entry CX1 baby super, based on Intel's Xeon processors, and its midrange and high-end massively parallel XT6m and XT6 supers, based on Advanced Micro Devices Opterons and which use Cray's own SeaStar2+ 2D and 3D torus interconnects to scale out.
The new machines are not based on Opteron processors and trimmed down SeaStar2+ interconnects, as El Reg speculated might be possible back in February, but on Intel's new "Westmere-EP" Xeon 5600 and impending "Nehalem-EX" Xeon 7500s, a possibility that was pondered as well. The new blade servers also deploy Nvidia's prior generation of Tesla graphics co-processors rather than the much-improved and still not shipping "Fermi" GPUs that were previewed at the SC09 supercomputing trade show last November.
There are three different models of the CX1000 machines, and only two of them are actually being announced today. The CX1000-C is a 7U chassis that holds 18 half-height two-socket blade servers based on the new six-core Xeon 5600 processors launched last week. There are ten blades along the bottom and eight blades along the top, with space for two fan blades for cooling in the center of the top part of the chassis. This chassis does not make use of the SeaStar2+ interconnect, but does have a 36-port quad data rate (40 Gb/sec) InfiniBand switch for lashing the blades together so they can run parallel computing workloads that use the ubiquitous Message Passing Interface (MPI) protocol for supercomputing.
There is an optional 24-port Gigabit Ethernet switch to hook the machines into Ethernet backbones as well. No word on who is making the InfiniBand and Ethernet switches used in the Cray chassis.
The CX1000-C chassis has one chassis management module and room for four hot-swap N+1 power supplies that together burn about 6500 watts and peak out at 8200 watts. The two fan blades help cool the chassis, and so do the two fans on each blade server.
The chassis also has an ultracapacitor module that allows the mini-super to ride out power outages that are 250 ms or less in duration. (This may not seem like a big deal until your super crashes after running for three months on a simulation and you have to go back and redo some of the calculations from a checkpoint because of a power glitch the human eye can barely perceive.)
The CX1000-C blade server is based on Intel's S5520 "Tylersburg" chipset and could, in theory, support both last year's Xeon 5500 and this year's Xeon 5600 processors. (It is hard to imagine why anyone would want the Xeon 5500s, given that the Xeon 5600's offer roughly 50 per cent more oomph and cost about the same.)
Cray will not support the fastest Xeon 5600 parts in the CX1000-C blades - that would be the six-core 3.33 GHz Xeon X5680 and the four-core 3.46 GHz X5677 - because at 130 watts they are too hot for the blade chassis. But Cray is supporting the six-core 2.93 GHz Xeon X5670s as well as other 95 watt and 80 watt parts with lower clock speeds. The CX1000-C blade has a dozen DDR3 memory sockets and supports up to 48 GB using 4 GB DIMMs. (Cray knows midrange HPC shops are too cheap to spend the extra money on 8 GB DIMMs today.) The blade has a Mellanox ConnectX mezzanine adapter to link out to the InfiniBand switch, a dual-port Gigabit Ethernet controller, and room for one small form factor SATA or SSD drive.