IBM Rounds Out Flex Systems With Xeon E5 Iron
August 13, 2012 Timothy Prickett Morgan
Big Blue added new machines to the Flex System lineup last week, but don’t get too excited. They were not Power7-based machines, or better still Power7+ nodes, but just X86-based nodes for the “Project Troy” modular system that the company debuted in April that are based on the latest Xeon E5 processors for two-socket and four-socket servers that were announced in May by Intel.
The Xeon E5-2600s are geared down versions of the Xeon E5-2600s that came out in March, sporting one fewer QuickPath Interconnect (QPI) link between the processor sockets and therefore lower memory capacity and bandwidth between the processors and in some cases lower performance. But they also come with lower price tags. The Xeon E5-4600s take the Xeon E5-2600s and use the two QPI links per socket to implement a much less expensive four-socket server than was possible using the larger Xeon X7 processors.
You can read my analysis of the Xeon E5-2400s and E5-4600s here so I don’t have to repeat all the same things.
The new Flex System x220 is a two-socket, single width node that looks very much like the original Flex System x240 node that was announced in April, except that it uses the E5-2400 processors instead of the E5-2600s. The processors are mounted in the center of the node before, with two mezzanine cards for linking to the midplane switch fabric at the back. The difference is that the Flex x220 only has six memory slots per socket instead of a dozen and is not so densely packed. IBM is supporting 16 GB memory sticks in the x220 node now, which means it tops out at 192 GB per node, but it could double that to 384 GB by allowing for 32 GB load-reduced DDR3 memory sticks to be used in the box. The Flex x220 has two hot-plug 2.5-inch disks in the front, like the x240 does, and there is a conversion kit that allows you to put four flash drives on the server lid (which ride above the memory) and replace the two disks with four more flash drives to give you 1.6 TB of flash storage inside the node to radically speed up data access. In the fall, IBM plans to move to 400 GB disks, shifting that up to 3.2 TB of flash per node. There is also a PCI-Express 3.0 x4 slot that can be used for a ServeRAID M5115 controller to RAID up those flash arrays.
This is an interesting bit of functionality, and I think that this flash kit should be made available for the Power7-based p260 node as well.
Ditto for the PCI-Express Expansion node, which was also announced last week, shown below.
As the name suggests, this expansion node plugs into the PCI-Express 3.0 bus on the Intel Xeon E5 processors and their related C600 chipset and extends it over to a node that has a PCI-Express 2.0 switch that has two x16 and two x8 slots on rise cards in the node. Because of power and thermal constraints, you can’t load this up with two Tesla GPU co-processors from Nvidia, but you can put in two flash units from Fusion-io or another vendor if you want. The Power-based nodes have a similar chipset that could, in theory, allow for the PCI-Express Expansion node to link to them, and it would be very interesting indeed to load up a two-socket Power7 machine with maybe four 400 GB flash drives (there is not room in the node for eight because of the size of the Power7 processors and their heat sinks)internal to the node plus some flash in the expansion node, too. This could result in a very powerful and compact OLTP machine if you paired it up with the internal Storwize V7000 disk array IBM will eventually deliver for the Flex System chassis. That would leave enough room in the 10U Flex System chassis for a few X86 nodes for Windows work.
The other new node is the double-wide Flex System x440, which is based on E5-4600 processors and which allows for up to 1.5 TB of main memory (using 32 GB LR-DIMMs) to be crammed into the node. The x440 node has two drive bays in the front and the same eight-drive flash kit and RAID controller can be used on it as on the x220 and x240. The p460 node tops out at 512 GB of main memory, which is not enough and will no doubt be addressed during the Power7+ upgrade cycle.
The new X86 nodes and the PCI-Express Expansion node will be available on August 24. Pricing was not announced, but I am a-looking. Fear not.