Posts tagged with Windows 7

Ralph Waldo Emerson once said “a foolish consistency is the hobgoblin of little minds.”

Well, it appears that Ralph never ran a data center.  Consistency is the holy grail of the data center, not the hobgoblin. When you have hundreds, or thousands of servers to keep track of, the more you can minimize the variances in hardware, the easier it is to manage the servers and your business.

Most IT teams typically spend the majority of their time managing software and not hardware. They realize that consistency can help reduce their software management tasks and make their lives easier.

Recently I read a blog on ZDnet where there is a potential concern about Windows XP compatibility on Windows 7 with some Intel desktop processors.  The blog author, Ed Bott states “In the case of Intel’s phenomenally confusing product matrix, VT support is added and removed from CPU models for reasons that have more to do with marketing than technology.”

(Read about our close collaboration with Microsoft to ensure stability and compatibility for Windows 7 in Nigel Dessau’s recent blog.)

How is this possibly tied to enterprise severs?  It’s all in the choices that your processor vendors make.  If they focus on consistency your life can be a lot easier; but some unnecessary forced choices can diminish your efficiency.

The newest Intel Xeon processors appear to suffer from a similar marketing decision.  At the top of the stack, the more expensive silicon has a full set of features.  But as you roll down the stack, away from the premium priced parts down to the mainstream parts (where the majority of the parts are sold) you see that many of the features and capabilities are either reduced or actually absent.

On some models the QPI bus speed is dropped, there are actually 3 different bus speeds depending on which model you buy.  Same with memory; three different memory speeds – meaning you have to stock multiple speeds of spares. Or you can choose to standardize on one speed, which means that you are either paying too much or compromising on the product, it’s your choice.  Cache is similar – sometimes it is the full amount, sometimes it is half of that.

What about software-visible features? Well, if you are tuning you applications to see a certain number of cores or to anticipate a particular performance level, then the fact that features like HyperThreading or Turbo are available on some processors and not others can create real server issues for you. Because not all Xeons have those features you start multiplying the number of software images that you have to maintain.  Or, to make your life easier, you just don’t support these features.

The AMD Opteron™ processor is different. When we design our processors, we hold the feature set consistent across the family.  That means customers can minimize their software changes and make systems easier to manage.  They can also do a better job of planning their deployments.  Knowing the features are consistent they can more accurately model the different performance levels for different processors. Cutting features like cache as you move down the stack makes it more difficult to accurately predict performance levels.

While some may counter that you can “scale performance” up and down the stack, this only works if your applications scale all resources equally.  If I/O and memory scale proportionately with CPU speed, then you are fine.  But what about web applications with their heavy I/O requirements but low CPU performance needs?  Well your choice is to overspend on the CPU to get the higher I/O performance or go with the lower priced CPU and compromise on the I/O performance that you likely need.  Neither choice is optimal.  That is why we drive for consistency. 

The reality of the situation is that having consistent features doesn’t have to prevent you from having a full stack of processors. Artificial limits only take away, they don’t enhance. And as we are finding out on the desktop side, the strategy could have downstream impacts that you hadn’t counted on.

John Fruehe is the Director of Business Development for Server/Workstation products at AMD. His postings are his own opinions and may not represent AMD’s positions, strategies or opinions. Links to third party sites are provided for convenience and unless explicitly stated, AMD is not responsible for the contents of such linked sites and no endorsement is implied.