Is ARM Nearing “Xeon-class” ? And Does It Matter?

I’ve often opined that ARM V8 server SOC’s would struggle to meet Intel Xeon head-on until a) appliedmicro_x_gene-1200x794they get a few micro-architecture revisions under their belts to improve per-core performance, and b) they can narrow the manufacturing gap to 14/16 nm, or perhaps even 10 nm.   Now,  Applied Micro is aiming to do just that with the X-Gene 3.  They have claimed this lofty goal before, with their 1st and then 2nd attempt at X-Gene’s custom cores. Now, it appears that their third generation custom-core SOC will (finally) deliver performance that is “well within range of Xeon E5 products”, according to a recently released report by the Linely Group, the widely read and respected publisher of the “The MicroProcessor Report.”

This announcement tees up 2 important topics.  1) Will X-Gene3 really deliver “Xeon-class” performance? and 2) does it matter?  i.e., do ARM server partners really need to chase Intel Xeon, or is there a market for less powerful “Atom-class” SOCs in the data center?   See my perspective on The Next Platform.


Has OpenPower Crushed ARM at Google?

Anyone who still doubted that large datacenters are serious about inducing  a competitive imagesCPU field certainly got a wakeup call last week when Rackspace and Google announced that they are teaming up to enable their use of OpenPower when IBM releases their POWER9 chip in late 2017.   Some have questioned whether this means ARM is now far behind,  and one does have to wonder how this could impact Qualcomm and Broadcom’s ARM Server SOC plans.   Let’s take a look at how this might play out.

First,  these pronouncements do not amount to an endorsement of OpenPower at the expense of other alternatives, namely ARM.   To the contrary,  they amount to an endorsement of HAVING CHOICE.  This is really great news,  showing that some of the industry’s titans are already preparing their software for alternative architectures and are willing to invest significant efforts to enable choice.

Second, one thing I learned at Calxeda and AMD was that large datacenters like Google, Facebook, Baidu, and even Microsoft are NOT fans, per se, of any particular architecture or supplier.  A “Fan” is someone who wants to see his team (chip) win, but these companies don’t give a whit who wins, so long as they can get more performance for less.  Its not that they don’t like Xeon, or ARM for that matter.  Xeon has been a unstoppable force in lowering datacenter costs for well over a decade.  But, everyone knows that competition spurs innovation and lowers costs. Google has repeatedly stated that they would adopt a new architecture if it delivered a 20% advantage over the incumbent (Intel Xeon).  But the only thing better than having a choice of 2 architectures for the datacenter is having 3,  and ARM is still the odd-on favorite to grab a share of the pie.

Finally, did ARM somehow blow their “lead”?  The fact is that OpenPower is ahead of ARM V8 64-bit implementations in terms of performance, and features.  However this comes at a significant cost and power premium over ARM implementations such as AMD, APMC, and CAVM.  its important to note that neither Google nor Rackspace are deploying the current POWER8 chips at this time in production workloads, presumably because of those premiums.  IBM clearly admitted that themselves by announcing a roadmap that has Scale Up and Scale Out (cheaper) versions of POWER9.  6965821-14600374310280457_origin

So where does this leave ARM and their partners?   Let’s be honest: ARM V8 implementations to date have been too wimpy in terms of per core performance,  and their energy efficiency for datacenter workloads has not kept up with Intel’s  Xeon D and Atom chips. We will see if Qualcomm can change that,  probably by the end of this year when many expect them to start sampling their 64 (!!)  core beast more widely.  However, going to 64 cores almost assures that this chip will not deliver the ~20 SpecINT per core performance threshold most hyper-scale and cloud users will demand, limiting its target market and SAM.  As for Broadcom, they have been strangely silent since their acquisition by Avago, causing many industry insiders to wonder whether the Vulcan chip will survive the acquisition budget and prioritization process. After all, the company had set expectations that Vulcan would ship by the end of LAST year, and I haven’t seen any evidence that this goal was met.

But lets face it, ARM does need to up their game with faster microarchitectures and more datacenter features, or OpenPower9 may carve out the lion’s share of the non-Xeon market in the 2019-20 timeframe. So, I  suspect we will be hearing a lot about “Ares”. ARM’s high end processor design for 10nm FF, this fall at TechCon,  if not sooner!  (They’d love to spoil Intel’s IDF party in August!)