ARM Takes on the Server Market: Why it Makes Sense
By Rob Gowin
Traditionally, the CPU market has been divided into three sectors: (1) embedded, (2) desktop, and (3) server. If we look at what’s going on with what Intel and ARM are doing in these markets, and especially if we look at what Intel is doing with the Atom and then consider the players and the interesting things about each market, I think that you’ll see that what ARM is doing here could stand to change a few things.
So Why Now?
With ARM clearly dominating the embedded processor space, they’re well positioned to make an attempt at breaking into other markets. It’s interesting that we’re now seeing the upper-end embedded processors crossing performance boundaries with low-end desktop CPUs. Because of this, high-end embedded processor designers like ARM are now finding themselves with access to new markets.
Why Not ARM on the Desktop?
I think that the low-end desktop space would be a huge challenge for ARM, mostly because of the dominance of Intel and Microsoft. If you look at the market, everybody keeps talking about ARM based netbooks coming out, but I haven’t seen any that are any good. Why is this? If I had to speculate, I would guess that there are a couple of issues here.
First off, these low-end desktops would have to run Linux (or Windows CE), since desktop editions of Windows are incapable of running on ARM. I think the consumer market has spoken and declared that they aren’t ready for Linux on the desktop.
Secondly, Microsoft has done a very good job at pricing low-end versions of Windows (~$100 OEM). So when consumers are building their netbooks, the price of adding Windows is low enough that it makes sense to pay the extra money and not have to learn a new OS.
Not only is ARM fighting against Intel and Microsoft, but the overall performance of ARM processors just isn’t up to the level of the Atom. A true desktop will require at least 2ghz speed, and ARM isn’t quite there yet.
Why Servers?
So the next step for ARM is then to look at the server space. This is a very interesting space for ARM, and I think that they’ve made the right call here. The server space is all about power consumption. In fact, a very large percentage of the budget for a typical datacenter is power. And since it’s really power consumption and low cost that have led ARM to dominate the embedded market, it just makes sense.
I think many server people have now reached the conclusion that you don’t need all that much processing power to serve up web pages. Scientific computing is another story of course, and ARM may get there one day. In fact Facebook is rumored to have started planning an ARM powered datacenter even though they publicly deny this.
Challenges Ahead
In the server space right now, the X86 giants are the dominant forces, but I think it’s interesting that the server space is sort of a graveyard for RISC architectures.While PowerPC, MIPS, and SPARC servers do continue to exist, they’ve given up much ground (especially in the webserver space) to Intel chips running Linux. So why does ARM think that they’re any different? I believe that there are two reasons.
First off – power consumption. In my opinion, it’s much easier to take a processor that was designed for low-power consumption and then increase the performance while relaxing some of the power features. This makes much more sense than trying to add aggressive power management features to a desktop processor. The other thing that I believe will help ARM be successful is that they have the ability to amortize their development cost for server chips over their entire catalog of embedded designs.
Is the Atom Only Good for Netbooks?
So where is Intel’s Atom in all of this? Intel has gotten very good at defending the low-end desktop space. But I think it’s interesting that we haven’t seen any Atom based smart phones yet. The reason for this is that the Atom and required chipsets just consume too much power. Intel is actively working on this now, but it’s my guess that it will be some time before (and if) they get it right.
Why don’t we see Atom based servers then? My guess is that the performance per watt just isn’t there and that the gain in power savings (versus a Xeon for example) isn’t worth the loss in performance. Maybe it will be worth it for ARM given their much lower power consumption, but this still remains to be seen.
