Let’s face it.  Virtualization is everywhere.  

Odds are there is something virtualized in your data center.  If not, it soon will be.  As more workloads become virtualized, chances are you are going to run out of “capacity” on your virtualization host.  When a host’s capacity is exhausted, 99% of the time it is because the host ran out of memory, not CPU.  Typically you would have to add another ESX host server when you run out of capacity.  When you do this, you are adding more hardware cost AND more virtualization licensing costs.  But what if you could simply add memory when you need it instead of buying more hardware.  Now you can with Dell’s FlexMem Bridge.

Background
You may recall that I mentioned the FlexMem Bridge technology in a previous post, but I don’t think I did it justice.  Before I describe what the FlexMem Bridge technology, let me provide some background.  With the Intel Xeon 7500 CPU (and in fact with all Intel Nehalem architectures), the memory is controlled by a memory controller located on the CPU.  Therefore you have to have a CPU in place to access the associated memory DIMMs…up until now.  Dell’s innovative approach removed the necessity to have a CPU in order to access the memory.

Introducing  Dell FlexMem Bridge
Dell’s FlexMem Bridge sits in CPU sockets #3 and #4 and connects a memory controller from CPU 1 to the memory DIMMs associated to CPU socket #3 and CPU 2 to the memory associated to CPU Socket #4.  

The FlexMem Bridge does two things:

1. It extends the Scalable Memory Interconnects (SMI) from CPU 1 and CPU 2 to the memory subsystem of CPU 3 and CPU 4.
2. It reroutes and terminates the 2nd Quick Path Interconnect (QPI) inter-processor communications links to provide optimal performance which would otherwise be disconnected in a 2 CPU configuration.

Sometimes it’s easier to view pictures than read descriptions, so take a look at the picture below for a diagram on how this works.

(A special thanks to Mike Roberts from Dell for assistance with the above info.)

Saving 50% on Virtualization Licensing
So how does this technology from Dell help you save money on virtualization licenses?  Simple - with Dell’s FlexMem Bridge technology, you only have to add memory, not more servers, when you need more capacity for VMs.  When you add only memory, you’re not increasing your CPU count, therefore your virtualization licensing stays the same.  No more buying extra servers just for the memory and no more buying more virtualization licenses.  In the future, if you find you have run out of CPU resources for your VM’s, you can remove the FlexMem bridges and replace with CPUs (for models with the Intel Xeon 7500 CPU only.) 

Dell FlexMem Bridge is available in the Dell PowerEdge 11G R810, R910 and M910 servers running the Intel Xeon 7500 and 6500 CPUs.

Looking through my previous posts it would appear that I’m against Dell’s blade server.  That’s not the case.  The reality is that it is hard to find good technical info on Dell’s product – that is until recently.  A search on SwagBucks.com led me to a little-known Dell website, called “Dell TechCenter Wiki“. 

The site, located at http://www.delltechcenter.com/, is a Dell sponsored wiki where you can find technical info on servers, storage, and even virtualization.  The wiki also provides recorded demos, white papers and even weekly chats with Dell experts to get your hard-to-answer questions answered.  Last week’s chat offered  an overview of new features available with the Dell Chassis Management Controller (CMC) for remote monitoring and access of system component information and status of Dell PowerEdge™ M1000e modular blade enclosures. 

As you can tell, this information can be extremely valueable to an IT professional with Dell blade servers, so I encourage you to check it out and let me know what you think.

BL2x220c G5 (2 server "nodes" shown)

HP’s BladeSystem server offering is quite extensive – everything from a 4 CPU Intel blade to an Itanium CPU blade, however their most well hidden, secret blade is their BL2x220c blade server.  Starting at $6,129, this blade server is an awesome feet of design because it is not just 1 server, it is 2 serversin 1 blade case – in a clam shell design (see below).  This means that in a HP C7000 BladeSystem chassis you could have 32 servers!    That’s 64 CPUs, 256 CORES, 2TB of RAM all in a 10U rack space.  That’s pretty impressive.  Let me break it down for you.  Each “node” on a single 2 node BL2x220c G5 server contains:

• Up to two Quad-Core Intel® Xeon® 5400 sequence processors
• Up to 32 GB (4 x 8 GB) of memory, supported by (4) slots of PC2-5300 Registered DIMMs, 667 MHz
• 1 non-hot plug small form factor SATA or Solid State hard drive
• Embedded Dual-port NC326i Gigabit Server Adapter
• One (1) I/O expansion slots via mezzanine card
• One (1) internal USB 2.0 connector for security key devices and USB drive keys

You may have noticed that this server is a “G5″ version and currently has the older Intel 5400 series processors.  Based on HP’s current blade offering, expect to see HP refresh of this server to a “G6″ model that will contain the Intel® Xeon® 5500 series processors.  Once that happens, I expect for more memoryslots to come with it, since the Intel® Xeon® 5500 series processors have 3 memory channels.  I’m guessing 12 memory slots “per node” or 24 memory slots per BL2x220c G6.  Purely speculation on my part, but it would make sense.  

Why do I consider this server to be one of HP’s best hidden secrets?  Simply because with that amount of server density, server processing power and server memory, the BL2x220c could become a perfect virtualization server.   Now if they’d only make a converged network adapter (CNA)…