Processor Whispers: Of stand-alone and standing alone
by Andreas Stiller
When you stand alone, a monopoly is particularly easy of course, and fittingly, Intel's next Xeon Phi processor can run in stand-alone mode.
If you plan to set up a big high-performance computer next year, you can chose between Haswell, Haswell and Haswell, well, maybe in blue, green or purple. That was the tenor of the complaints of many representatives of data centres at the International Supercomputing Conference in Leipzig, Germany. The dominance of Intel in the HPC sector has become overwhelming: 98 percent of the new systems in the Top500 list rely on Intel processors. Numbers like that are usually reserved for election results in authoritative regimes – or the election of Angela Merkel as chairwoman of the German political party CDU.
No one but Intel considers such dominance to be a healthy development of the market. On the other hand, Intel's excuse, "It's not our fault that the others can't keep up", is quite reasonable. AMD, in any case, seems to have given up on the high-end servers and is now focusing on microservers and video game consoles.
While, on the occasion of ISC, AMD released a new server roadmap, the company was not present at the conference. Well, what would they have been able to present for this high-end segment? Neither Opterons with Steamroller architecture nor PCI Express 3.0 are anywhere in sight in the upper house. A new Piledriver codenamed Warsaw is scheduled to offer a slightly improved energy efficiency and better TCO values in 2014, and that's it. Much more interesting is the "lesser" roadmap for single-socket processors – for webservers for example. Here, AMD plans to offer a total of three entirely different processor architectures in 2014, with and without graphics (GCN). So in this regard, it is Intel that won't be able to keep up.
First, the recently announced Opterons X1150 and X1250 (Kyoto) with four Jaguar cores will arrive, the latter as APU with graphics, manufactured in 28nm. In the second half of 2014, the Seattle with 8 and 16 ARM Cortex-A57 cores is supposed to follow. Especially interesting is its interconnect. Besides the conventional 10GbE, AMD is equipping the Seattle with Freedom Fabric, the interconnect technology it got hold of by absorbing SeaMicro. With more than 2GHz of clock speed, the Seattle is supposed to deliver between two and four times the performance of the x86 series, coupled with a significantly improved energy efficiency.
And there it is, amongst the small servers, the Steamroller we were looking for, including PCI Express 3.0. It is set to launch with four cores – or, from the HPC point of view, with two FPUs – under the codename Berlin. An APU with GCN will additionally make it an interesting option for small, inexpensive workstations.
As AMD does not have a competitor for Intel's Xeon E5 line-up, Intel has to create competition on its own. And so Intel's manager of technical computing, Rajeeb Hazra, surprised the audience during the less surprising presentation of the new Xeon Phi versions by saying that the successor, codenamed Knights Landing and manufactured in the 14nm process, was also designed for to work in a stand-alone mode. So it can, or more precisely is allowed to, boot on its own. Behind the scenes, it was said that this feature was the cause of fierce internal debates at Intel – after all, the Xeon department was not keen on competition from within the company, but if there is none from without ... Anyway, Eurotech had already shown that the current Xeon Phi can be run in stand-alone mode with a little FPGA help.
Now I stand alone ...*
That Knights Landing will, conveniently, be compatible with the Xeon socket is something that Hazra did not want to confirm yet – but some OEM partners at ISC did so for him. Neither did Hazra want to give any details on the new x86 core. For some time now, there have been reports that Intel is going to move away from the antiquated Pentium in favour of the current Atom, probably with a Silvermont-like out-of-order architecture.
Additionally, it is believed to arrive with stacked memory inside the package. The size is still unknown, but it probably will be one or more gigabytes. The bandwidth of in-package DRAM, as Intel developers pointed out in other ISC sessions, is supposed to be eight to ten times higher than with external memory – that certainly raises expectations. A number cruncher with significantly more than the current 62 cores is expected at the end of next year.
Through the memories ...
In the present, it is the Xeon Phi codenamed Knights Corner that is really becoming available as up until now they had been rather difficult to obtain. Most likely the yield was just too low to distill 60 working cores at only 225 watts TDP. But now the Xeon Phi 3120A/P is on the market, with only 57 active cores, 6GB of memory and an energy consumption range of up to 300 watts TDP. In return, it costs $1000 less than the 60-core Xeon Phi 5110 with 8GB. And for the moneyed buyer, there is a new luxury version, Xeon Phi 7120, with 61 cores, 1.238GHz and 16GB of memory that reaches 1.333GHz in turbo mode. However, the remarkable price of $4129 means that, in comparison to the 3120 card, the price/performance relationship is worse by a factor of two.
* Yes, yes, Bob Marley, who died the year that IBM invented the PC ...