Up or Out?

by Scott Kantner, June 26th, 2009 in Hosting, Servers

I recently read a post that took a new twist on the long-term debate over whether it’s better to scale up (buy bigger servers) or scale out (buy more servers).  Traditionally this battle has been fought mostly on the technical considerations only.  ”Which is better for processing the real-time inventory of my growing  Dippin’ Dots empire vs. the fast serving of web  pages on my trendy social site?”

DIPPIN' DOTS BANANA SPLIT

The conversation is often reduced to raw number crunching power vs. the benefits of highly parallel processing or high availability.  But in this era of sacrifice, we might want to take a look at the oft-overlooked cost factors lurking behind the curtain.  Following the framework of the aforementioned post, let’s consider the costs using IBM hardware.

First, we fire up IBM’s server configuration tool and build a big dreadnought-class server with an x3950 M2:

  • 4 CPU sockets (using 6-core processors)
  • 32 memory sockets
  • 4 drive bays
  • 2 power supplies
  • 4U

Total Price:  $68,429  MSRP.  In Pennsylvania, we throw on another 6% for the Governor, so the number rounds to $72,500.   Sure enough, scaling up has the hefty price tag one would expect.

If instead we were to scale out, what kind of horsepower could we get for the same money?  Taking a trip to the other end of the product line, we find the modest x3250 M2:

  • 1 CPU socket (using a 4 core processor)
  • 4 memory sockets
  • 2 drive bays
  • 1 power supply
  • 1U

Total Price: $2,431 MSRP.  Allowing again for the Governor, we come in at $2,575, which means that for the same $72,500 we could buy 28 of these unassuming smaller servers.

So, if we decide to go shopping to IBM with $72,500 as our budget, what can we get for our money?

: ———— Scaling Up           Scaling Out

CPU’s               24                          112

RAM              256GB                   224GB

Disk               1.2TB                      28TB

It would seem that scaling out puts more resources in our data center for the same money.  Score 1 for scaling out.

Now let’s take a look at things from the software angle:

:—————————–   Scaling Up             Scaling Out

Windows 2K8 Server*            $2,515                     $20,524

SQL-Server                              $7,400                    $16,800

Our quick mental math says that scaling out costs nearly 4 times as much in software.  Score 1 for scaling up.

And now for the tie breaker, let’s examine operational power costs, assuming the boxes run on average at 50% of peak and without factoring in cooling:

——————-    Scaling Up           Scaling Out

Peak Watts                1440w                     9,828w

Power Cost/Year        $441                       $3,013

Scaling out is an order of magnitude higher in power costs.  Final score: Scaling up appears to win in a narrow 2-1 victory.

Having seen the costs, which approach seems to make more sense?   If you object to this question, you’re quite right to do so.  From a strictly financial point of view, scaling up seems to be way the go, unless you decide to level the playing field by zeroing the software costs with open source (e.g. Linux and PostgreSQL).  Scaling out becomes more financially appealing when open source is in play, which is what we often find in places like Google.

Of course, the decision can’t be made solely from a financial point of view, but prior to this exercise  have you ever even considered these hidden-in-plain-sight costs?  Ultimately the decision still does still come down to your particular business needs which must be discussed on the technical requirements involved.   Watching your team whiteboard the various options can sometimes be more tedious than reading Klingon poetry,

klingon2

but you need to let the team work through both the technical and cost considerations to arrive at the best solution.

There are two take-aways from this example.  The first is that when the technical requirements don’t point hard in either direction, you may be able to appeal to cost to help arbitrate the decision.  The second is that you really don’t need to make these types of decisions anymore.  The infrastructure utility trend is already in motion and is gaining momentum.   Before investing significant capital of any scale, consider deploying new applications in a professional hosting data center. Outsource these ongoing scaling decisions to others while you focus on the bigger picture of providing the right applications for your business.

//spk

* Please don’t flame me with comments like “How’d you get those prices, we only pay $20 for Win2K8 server?”   I haven’t spent the four years of education required to be fully conversant in the Microsoft  Licensing program, which is more complex and complicated than ancient Hebrew Law.  These prices were based on recent customer quotes and internal pricing from our distributors.

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