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November 15, 2009

OpenFabrics Alliance Weaves Its Story at SC09

Nicole Hemsoth

We have developed something of a tradition at HPCwire in the weeks leading up to each year’s SC conference; we interview the chairman of the OpenFabrics Alliance (OFA). We realized five years ago the major impact that OFA’s free, open-source software stack could have on the HPC community, and we want to keep our readers updated on the work being done by OFA as well as the latest enhancements to the OpenFabrics Software stack.

Jim Ryan of Intel has been the OFA’s chair all these years, and our annual interview with Jim was as interesting as ever.

HPCwire: Good to talk with you again this year Jim. OFA members have been part of SCinet each year at SC. I suspect that is to allow exhibitors to show attendees the latest capabilities they’ve developed to leverage OpenFabrics Software on InfiniBand and Ethernet networks. What is being shown this year?

Jim Ryan: For the past four years, SCinet’s OpenFabrics Team has built networks at SC so exhibitors can demonstrate their products and research, including interconnects for servers, clusters, storage and file systems. This year we are setting records with the number of industry participants (18), the highest speed (IB 12X at 120Gbps) and the range of innovative applications that are on display.

OFA is collaborating with the HPC Advisory Council and together we are showing:

— Remote Desktop over InfiniBand (RDI) that enables live desktop sharing at high speeds between tens of participants.
— Direct Transport Compositor (DTC) that provides real-time rendering of a PSA Peugeot Citroen automotive CAD model in 2D/3D.
— New high-bandwidth MPI technology that takes advantage of 120Gbps data rates from a single server.

In addition to these demos, any connected exhibitors can demonstrate interoperability using OpenFabrics Software for Linux or Windows on the same IB network to exploit the full range of RDMA Application Services (R-DMAS). These include all the MPIs (e.g., Open, MVapich, Intel, HP), uDAPL, accelerated IP networking, Sockets using Oracle’s RDS, SRP and iSCSI for block storage, and file systems using any of NFS, Gluster, IBRIX, Lustre, and GPFS.

HPCwire: What else is on tap for OFA at SC09?

Ryan: We’ll be hosting a Birds of a Feather session at 5:30 p.m. on November 18 in Room PB251. At that time, we’ll have a very important announcement to make about a significant new member.

During the session, we’ll also announce the status, features and schedule for the next software releases: OFED 1.5 for Linux and WinOF 2.1 for Windows. Attendees will have the opportunity to ask OFA developers questions about many topics, such as improved routing for IB, routing options in Ethernet for clusters, the status of iWARP, and support in Linux environments for IEEE Datacenter Bridging on 10 Gigabit Ethernet for clustering. We’ll also be talking about our scalability road map, including plans for evolving OpenFabrics to be the interconnect software of choice for ExtremeScale.

On the exhibit floor, OFA is sharing Booth 137 with the InfiniBand Trade Association. There will be live demos and talks by our members as well as a joint presentation with the IBTA at 11:30 a.m. on November 17 at the Exhibitor Forum.

HPCwire: Can you tell our readers how OpenFabrics Software benefits end users?

Ryan: Well, the benefits must be pretty compelling because analysts estimate about 60 percent of all new HPC systems worldwide utilize OpenFabrics Software. We’re also seeing adoption in the enterprise where our software is being used to achieve high-speed server-to-storage communication and to implement unified fabrics on IB and low-latency Ethernet networks.

By linking applications to any of the RDMA services in the OpenFabrics Software, users can be assured they are getting the highest achievable data-transfer rates, the lowest achievable latencies (1 to 3 microseconds) and the most efficient computing (75 to 85 percent server utilization) for a full range of virtualization and enterprise datacenter applications, cloud computing, and simulation/modeling.

As an example, Oracle advertises RAC with IB as delivering a 10X improvement in application speed at half the hardware cost of traditional implementations. That’s made possible by OpenFabrics Software.

Users also gain the freedom of choice over a wide range of operating systems, computer architectures, and network and storage technologies. In each of these dimensions, we are seeing increased support from major vendors such as Dell, HP, IBM and Sun. All offer OpenFabrics Software with appropriate products. They also provide technical support.

HPCwire: Who are some of the members of the OpenFabrics Alliance?

Ryan: The primary network and interconnect vendors include Cisco, Mellanox, QLogic and Voltaire — all of which offer both Ethernet and InfiniBand products. The server vendors include Cray, HP, IBM and Sun. Storage is represented by DDN, LSI and NetApp, and databases by Oracle. Among the smaller members are Endace, System Fabric Works and Xsigo. Large users are represented by the DOE labs — Livermore, Los Alamos and Sandia. And for processors, we have Intel and AMD.

HPCwire: We hear a lot about Ethernet becoming the “converged network” that will be the only interconnect users need. How is OpenFabrics viewing this advocacy from certain vendors and what range of networks or fabrics are you supporting?

Ryan: As you know, InfiniBand has been the basis of our early work. Right from its inception 10 years ago, IB was conceived and architected as a unified fabric for all HPC and datacenter applications. In HPC, this vision is starting to take shape now. What people frequently overlook is that IB is architected in layers — application interfaces at the top, software in the middle and hardware at the bottom. Much of the value in IB is in the software which implements zero copy transfers, RDMA, APIs in the kernel, user space and reliable transports. So when we adopted iWARP a couple of years back that allowed the existing software to be integrated to provide an RDMA capability over Ethernet.

iWARP uses TCP/IP (that’s Layers 4 and 3) and Ethernet (Layer 2) as its underlying transport with the TCP/IP outboard on an adapter. This is excellent for users who need to maintain TCP/IP with store and forward routing of messages within their datacenters. At SC09, you can see iWARP demos at booths hosted by the Ethernet Alliance, Intel, Chelsio and others.

Now some organizations are starting to realize “Ethernet only” is all they need within their datacenters, particularly with the emergence of low-latency cut-through switches and DCB from the IEEE. Within OFA, some members have implemented the software from IB directly on both hardware-accelerated and legacy-Ethernet adapters and chipsets without any TCP or IP. It’s too early to tell right now how this will be accepted by vendors and users, but at SC you’ll be able to see a demo at the Ethernet Alliance booth.

HPCwire: What is OFA currently focused on?

Ryan: Let’s start with HPC. Reliable, efficient, scalable software for IB clusters that have 10 to 100,000 nodes is what our founding DOE Lab members are telling us they need in the next year or two. So that’s a high priority that will be of value to all users of OpenFabrics Software. It will be also become essential as IB speeds up to 40-80-120 gigabits with latencies below 1 microsecond.

I think we can all see in the next couple of years 10 Gigabit Ethernet prices for cluster connections (switch port and adapter/chip) dropping below $1,000. Then we will start to see an enormous percentage of clusters and datacenters migrate from their 1 Gigabit Ethernet networks to 10 gigabits. We believe that’s when RDMA over Ethernet, with or without TCP/IP, will hit its stride and converged or unified fabrics will become de rigeur. In the OFA, we are preparing both our Linux and Windows stacks to be the software of choice for this migration. OpenFabrics Software will be particularly valuable for organizations that need to support both legacy applications and RDMA applications.

Also in coming years, as we embark on extreme scalability in HPC, and virtualization and fabric unification penetrate deeper into datacenters, the OpenFabrics RDMA storage application services will become more important. It will enable traditional fibre channel SAN, iSCSI and NAS protocols to be used on the unified fabric, whether it be Ethernet or InfiniBand.

Jim, thanks for giving HPCwire’s readers such a detailed view into the OFA. You and your members have shown us the value of partnership and collaboration amongst vendors, developers and customers in an open-source community. See you in Portland at SC09 on November 15.

To keep up with the latest news from the OFA, goto or join the OpenFabrics Alliance Facebook group.