AMD, Samsung must be ARMed to the teeth to oust Intel servers
The attack always comes from below - and at the edges
ARM hegemony: The other possibility
This is an interesting thesis, but it is not the only kind of homogeneity that is possible. El Reg would argue that you could build an end-to-end ARM architecture, based on either Windows (if Microsoft ever gets around to putting Server 2012 on ARM chips) or Linux (Android on user devices and Red Hat Enterprise Linux, Ubuntu Server, and SUSE Linux Enterprise Server on the back-end machines). And this could give developers a kind of heterogeneity that spans all kinds of devices. In this scenario, it is x86 that is the odd instruction set out.
This scenario is no forgone conclusion, mind you. It is just a possibility, and perhaps a remote one. But that doesn't mean x86 chips will rule the data centre forever, any more than mainframes did.
The typical argument against the ARM architecture is that 32-bit processing and memory addressing in Cortex-A9 cores, or 32-bit processing and 40-bit physical memory addressing in Cortex-A15 cores, is not enough to contend against a Xeon or Opteron rival. It is helpful to remember that Xeon chips were 32-bit machines many years after other processors had jumped to 64-bits.
As students of history all know, the attack always comes from the bottom in any market, and often from an unintended competitor that was initially focussed on a different set of engineering problems and products. Intel was dragged into the x86 server business two decades ago by customers looking for alternatives to RISC-powered Unix machines, as much as it has been dragged into making microservers based on server-specific Atom processors this year.
Similarly, the ARM collective has been dragged into the server arena because of power and cooling issues in hyperscale data centres. And it is obvious that this nascent market is ready for science projects using sub-64-bit processors, but not much else today. Volume ramping of ARM servers is not going to start for some time. Maybe it will happen in 2013, but it is probably more likely in 2014 when the first 64-bit chips are available and the enterprise-grade variants of Linux and maybe even Windows Server 2012 R2 are available on the most important chips from Calxeda, Applied Micro Circuits, AMD, Marvell, Cavium, and maybe the wildcard Samsung Electronics if it jumps onto the ARM server chip bandwagon.
But just like it was foolish to count out a bunch of idealists building Linux when Microsoft was positioning Windows as an alternative to Unix and proprietary operating systems, it is foolish to think that a bunch of scrappy and not terribly profitable ARM server companies can pull the same trick and take some share away from Intel not just on user devices as the type of devices has expanded, but in the core server, storage, and networking business that Intel hopes to double to $20bn in revenues by 2015.
"If this is going to be a fair fight, it is time for the big boys," Ian Ferguson, director of server systems and ecosystems at ARM Holdings, told El Reg at a meeting during Intel Developer Forum back in September. He did not name any names, but there were rumors going around that AMD would become an official ARM server chip licensee. Obviously that has happened, and AMD is now projecting it can get processors based on the 64-bit Cortex-A50 "Atlas" design and integrated with the Freedom fabric interconnect at the heart of the SeaMicro servers by 2014. Back in April, there was chatter that Samsung wanted to get into ARM servers, too.
These are presumably the big boys Ferguson was referring to, but the big server OEMs are also going to have to be convinced to adopt ARM server chips in their designs for this market to be more than a niche used by those who adopt SeaMicro boxes, Dell or HP bespoke machines, or a bunch of niche players that have committed to Calxeda EnergyCore processors.
Intel has been very clear that it believes that the microserver market might grow to account for about 10 percent of server shipments (and a much lower slice of revenues) over the next few years. And in Intel's mind, microservers generally means low-power Xeon and Atom processors in single-socket machines with limited main memory. ARM doesn't think the market is that small.
"I think there is a much bigger opportunity than single digits," explained Simon Segars, general manager of the processor and physical IP divisions at ARM Holdings, at the AMD-ARM partnership launch this Monday. "Tens of per cent over time is where I think the market can get to."
All we can say for sure is that this is going to be a prolonged and entertaining battle, and Intel is not going to relinquish a millimetre of ground in the data centre without a fight. The ARM collective better get its engineering on, and pick fab partners that can deliver on schedule with no bugs. ®