One of the developing trends in computing, relevant to both enterprise and service providers alike, is the notion of workload-specific or application-centric computing architectures. These architectures, optimized for specific workloads, promise improved efficiencies for running their targeted workloads, and by extension the services that they support. Earlier this year we covered the basics of this concept in “Optimize Scalable Workload-Specific Infrastructure for Customer Experiences”, and this week HP has announced a pair of server cartridges for their Moonshot system that exemplify this concept, as well as being representative of the next wave of ARM products that will emerge during the remainder of 2014 and into 2015 to tilt once more at the x86 windmill that currently dominates the computing landscape.
Specifically, HP has announced the ProLiant m400 Server Cartridge (m400) and the ProLiant m800 Server Cartridge (m800), both ARM-based servers packaged as cartridges for the HP Moonshot system, which can hold up to 45 of these cartridges in its approximately 4U enclosure. These servers are interesting from two perspectives – that they are both ARM-based products, one being the first tier-1 vendor offering of a 64-bit ARM CPU and that they are both being introduced with a specific workload target in mind for which they have been specifically optimized.
As the new year looms, thoughts turn once again to our annual reading of the tea leaves, in this case focused on what I see coming in server land. We’ve just published the full report, Predictions for 2014: Servers & Data Centers, but as teaser, here are a few of the major highlights from the report:
1. Increasing choices in form factor and packaging – I&O pros will have to cope with a proliferation of new form factors, some optimized for dense low-power cloud workloads, some for general purpose legacy IT, and some for horizontal VM clusters (or internal cloud if you prefer). These will continue to appear in an increasing number of variants.
2. ARM – Make or break time is coming, depending on the success of coming 64-bit ARM CPU/SOC designs with full server feature sets including VM support.
3. The beat goes on – Major turn of the great wheel coming for server CPUs in early 2014.
4. Huge potential disruption in flash architecture – Introduction of flash in main memory DIMM slots has the potential to completely disrupt how flash is used in storage tiers, and potentially can break the current storage tiering model, initially physically with the potential to ripple through memory architectures.
So far the latter seems to be the prevailing trend as the majority of public cloud platforms and private cloud software solutions start with the foundation of server virtualization. The bare metal options are being positioned more for two purposes:
Auto-provisioning new nodes ofthe cloud - bare metal installation of the cloud solution and the hypervisor
New compute resource types inthe cloud - using new automation capabilities to add a complete physical server to a customer’s cloud tenancy, as if it were just another virtual machine.
Yesterday Intel had a major press and analyst event in San Francisco to talk about their vision for the future of the data center, anchored on what has become in many eyes the virtuous cycle of future infrastructure demand – mobile devices and “the Internet of things” driving cloud resource consumption, which in turn spews out big data which spawns storage and the requirement for yet more computing to analyze it. As usual with these kinds of events from Intel, it was long on serious vision, and strong on strategic positioning but a bit parsimonious on actual future product information with a couple of interesting exceptions.
Content and Core Topics:
No major surprises on the underlying demand-side drivers. The the proliferation of mobile device, the impending Internet of Things and the mountains of big data that they generate will combine to continue to increase demand for cloud-resident infrastructure, particularly servers and storage, both of which present Intel with an opportunity to sell semiconductors. Needless to say, Intel laced their presentations with frequent reminders about who was the king of semiconductor manufacturingJ
Background — High Performance Attached Processors Handicapped By Architecture
The application of high-performance accelerators, notably GPUs, GPGPUs (APUs in AMD terminology) to a variety of computing problems has blossomed over the last decade, resulting in ever more affordable compute power for both horizon and mundane problems, along with growing revenue streams for a growing industry ecosystem. Adding heat to an already active mix, Intel’s Xeon Phi accelerators, the most recent addition to the GPU ecosystem, have the potential to speed adoption even further due to hoped-for synergies generated by the immense universe of x86 code that could potentially run on the Xeon Phi cores.
However, despite any potential synergies, GPUs (I will use this term generically to refer to all forms of these attached accelerators as they currently exist in the market) suffer from a fundamental architectural problem — they are very distant, in terms of latency, from the main scalar system memory and are not part of the coherent memory domain. This in turn has major impacts on performance, cost, design of the GPUs, and the structure of the algorithms:
Performance — The latency for memory accesses generally dictated by PCIe latencies, which while much improved over previous generations, are a factor of 100 or more longer than latency from coherent cache or local scalar CPU memory. While clever design and programming, such as overlapping and buffering multiple transfers can hide the latency in a series of transfers, it is difficult to hide the latency for an initial block of data. Even AMD’s integrated APUs, in which the GPU elements are on a common die, do not share a common memory space, and explicit transfers are made in and out of the APU memory.
HP today announced the Moonshot 1500 server, their first official volume product in the Project Moonshot server product family (the initial Redstone, a Calxeda ARM-based server, was only available in limited quantities as a development system), and it represents both a significant product today and a major stake in the ground for future products, both from HP and eventually from competitors. It’s initial attractions – an extreme density low power x86 server platform for a variety of low-to-midrange CPU workloads – hides the fact that it is probably a blueprint for both a family of future products from HP as well as similar products from other vendors.
Geek Stuff – What was Announced
The Moonshot 1500 is a 4.3U enclosure that can contain up to 45 plug-in server cartridges, each one a complete server node with a dual-core Intel Atom 1200 CPU, up to 8 GB of memory and a single disk or SSD device, up to 1 TB, and the servers share common power supplies and cooling. But beyond the density, the real attraction of the MS1500 is its scalable fabric and CPU-agnostic architecture. Embedded in the chassis are multiple fabrics for storage, management and network giving the MS1500 (my acronym, not an official HP label) some of the advantages of a blade server without the advanced management capabilities. At initial shipment, only the network and management fabric will be enabled by the system firmware, with each chassis having up two Gb Ethernet switches (technically they can be configured with one, but nobody will do so), allowing the 45 servers to share uplinks to the enterprise network.
Today’s announcements at the Open Compute Project (OCP) 2013 Summit could be considered as tangible markers for the OCP crossing the line into real relevance as an important influence on emerging hyper-scale and cloud computing as well as having a potential bleed-through into the world of enterprise data centers and computing. This is obviously a subjective viewpoint – there is no objective standard for relevance, only post-facto recognition that something was important or not. But in this case I’m going to stick my neck out and predict that OCP will have some influence and will be a sticky presence in the industry for many years.
Even if their specs (which look generally quite good) do not get picked up verbatim, they will act as an influence on major vendors who will, much like the auto industry in the 1970s, get the message that there is a market for economical “low-frills” alternatives.
Major OCP Initiatives
To date, OCP has announced a number of useful hardware specifications, including:
Earlier this week, in conjunction with ARM Holdings plc’s announcement of the upcoming Cortex A53 and A57, full 64-bit CPU implementations based on the ARM V8 specification, AMD also announced that it would be designing and selling SOC (System On a Chip) products based on this technology in 2014, roughly coinciding with availability of 64-bit parts from ARM and other partners.
This is a major event in the ARM ecosystem. AMD, while much smaller than Intel, is still a multi-billion-dollar enterprise, and for the second largest vendor of x86 chips to also throw its hat into the ARM ecosystem and potentially compete with its own mainstream server and desktop CPU business is an aggressive move on the part of AMD management that carries some risk and much potential advantage.
Reduced to its essentials, what AMD announced (and in some cases hinted at):
Intention to produce A53/A57 SOC modules for multiple server segments. There was no formal statement of intentions regarding tablet/mobile devices, but it doesn’t take a rocket scientist to figure out that AMD wants a piece of this market, and ARM is a way to participate.
The announcement is wider that just the SOC silicon. AMD also hinted at making a range of IP, including its fabric architecture from the SeaMicro architecture, available in the form of “reusable IP blocks.” My interpretation is that it intends to make the fabric, reference architectures, and various SOCs available to its hardware system partners.
Earlier this week Dell joined arch-competitor HP in endorsing ARM as a potential platform for scale-out workloads by announcing “Copper,” an ARM-based version of its PowerEdge-C dense server product line. Dell’s announcement and positioning, while a little less high-profile than HP’s February announcement, is intended to serve the same purpose — to enable an ARM ecosystem by providing a platform for exploring ARM workloads and to gain a visible presence in the event that it begins to take off.
Dell’s platform is based on a four-core Marvell ARM V7 SOC implementation, which it claims is somewhat higher performance than the Calxeda part, although drawing more power, at 15W per node (including RAM and local disk). The server uses the PowerEdge-C form factor of 12 vertically mounted server modules in a 3U enclosure, each with four server nodes on them for a total of 48 servers/192 cores in a 3U enclosure. In a departure from other PowerEdge-C products, the Copper server has integrated L2 network connectivity spanning all servers, so that the unit will be able to serve as a low-cost test bed for clustered applications without external switches.
Dell is offering this server to selected customers, not as a GA product, along with open source versions of the LAMP stack, Crowbar, and Hadoop. Currently Cannonical is supplying Ubuntu for ARM servers, and Dell is actively working with other partners. Dell expects to see OpenStack available for demos in May, and there is an active Fedora project underway as well.
I said last year that this would happen sometime in the first half of this year, but for some reason my colleagues and clients have kept asking me exactly when we would see a real ARM server running a real OS. How about now?
To copy from Calxeda’s most recent blog post:
“This week, Calxeda is showing a live Calxeda cluster running Ubuntu 12.04 LTS on real EnergyCore hardware at the Ubuntu Developer and Cloud Summit events in Oakland, CA. … This is the real deal; quad-core, w/ 4MB cache, secure management engine, and Calxeda’s fabric all up and running.”
This is a significant milestone for many reasons. It proves that Calxeda can indeed deliver a working server based on its scalable fabric architecture, although having HP signing up as a partner meant that this was essentially a non-issue, but still, proof is good. It also establishes that at least one Linux distribution provider, in this case Ubuntu, is willing to provide a real supported distribution. My guess is that Red Hat and Centos will jump on the bus fairly soon as well.
Most importantly, we can get on with the important work of characterizing real benchmarks on real systems with real OS support. HP’s discovery centers will certainly play a part in this process as well, and I am willing to bet that by the end of the summer we will have some compelling data on whether the ARM server will deliver on its performance and energy efficiency promises. It’s not a slam dunk guaranteed win – Intel has been steadily ratcheting up its energy efficiency, and the latest generation of x86 server from HP, IBM, Dell, and others show promise of much better throughput per watt than their predecessors. Add to that the demonstration of a Xeon-based system by Sea Micro (ironically now owned by AMD) that delivered Xeon CPUs at a 10 W per CPU power overhead, an unheard of efficiency.