March 1, 2023 — In the latest episode of the Let’s Talk Exascale Podcast, Scott Gibson welcomes guest Katherine Riley, the ALCF’s director of science. Riley leads a team of computational science experts who work with facility users to maximize their use of ALCF computing resources. She has been at the ALCF since 2007 and has the distinction of being one of the facility’s first hires.

Gibson and Riley discuss a variety of topics:

• Who the ALCF serves and the ways users are granted access to the facility’s systems.
• The types of research conducted using ALCF systems.
• Some of the major activities currently taking place at the ALCF.
• A summary of the innovations that Aurora will offer.
• Progress in deploying Aurora.
• Argonne’s role in partnering with ECP.
• The impact ECP’s products are already having on the high-performance computing and research communities.
• What ECP will leave in its wake and the “then and now” perspective on how it has changed high-performance computing since the project began.
• And thoughts about maintaining the continuity of ECP’s work after the project ends.

Argonne National Laboratory and the Argonne Leadership Computing Facility, or ALCF, have been an essential part of ECP since the project’s planning stages. Along with the other DOE computing facilities, Argonne has participated and led in all components of ECP. Additionally, the first director of ECP was Paul Messina, an Argonne Distinguished Fellow and Argonne Associate.

The ALCF, a DOE Office of Science user facility, enables breakthroughs in science and engineering by providing supercomputing resources and expertise to the research community. Led by Director Michael Papka, the ALCF is supported by DOE’s Advanced Scientific Computing Research, or ASCR, program. The ALCF and its partner organization, the Oak Ridge Leadership Computing Facility, or OLCF, at Oak Ridge National Laboratory, operate leadership-class supercomputers that are orders of magnitude more powerful than the systems typically used in open science.

Argonne is the process of deploying the Aurora exascale-class supercomputer. Aurora will support advanced machine learning and data science workloads alongside more traditional modeling and simulation campaigns.

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Scott: As already mentioned, Katherine has been with the ALCF since its earliest days.

Katherine: I am the director of science at the ALCF. And I really started in this whole field … my professional life has really been spent in the field of high-performance computing [HPC]. And this started because as I was working toward a degree in astrophysics and applied math, I got very distracted. I got, in the end, not a little distracted but fully diverted into understanding what you need to do to a science application to work on an HPC system. This was in the mid-to-late nineties, and I was working with a project that many ECP listeners might have heard of, which was the Flash project at the University of Chicago. And the reason I specifically named that is that was a really phenomenal experience to have, because it was one of the rare circumstances where a project had a substantial amount of funding not just for the science that the team needed to accomplish but also to design and architect and create a real science application tool that was well architected. And that’s really what pulled me off, sort of the process of designing basically good scientific software that performed well for the systems of that time was really fascinating and was and is a hard problem and, frankly, didn’t receive a whole bunch of attention. So that’s really what started me on this, and this, as I said, was quite a while ago.  And really, for someone who is interested in that, the natural process is you end up at a national lab. It is not the only place you could end up but certainly a very natural place you can end up.

So I’ve been at the Argonne Leadership Computing Facility since it was started. I initially started working as what we call our catalyst, our science consultant. These are the people who are collaborating with people in various different fields to get their application ready to think about how they’re using these big systems. And then it’s just evolved over time to the director of science position. And here, the big one-liner really is that the director of science makes sure we deliver on our mission, and our mission, which we’ll get to, is really to deliver science on these systems. We don’t build these big systems for the fun of building these big systems. It’s to deliver science, impactful research that you could not do otherwise.

And so sometimes that is overseeing how we design these systems and what we’re putting on these systems, how we’re actually executing things in production, but it’s also thinking ahead into our future systems and how we get science ready to go on these—pretty tricky—supercomputers.

Scott: When did the ALCF start, and what’s the story behind it?

Katherine: That’s a fantastic question. It’s about 2006 that the ALCF was founded, and that was actually the first year that we joined sort of the larger pool of things that the Department of Energy was building at that time to serve the open-science community in terms of science. That start is actually is a really interesting one, I think, because around 2004, Congress responded to Japan building the Earth Simulator, and we as a country really wanted to respond to that because it so outpaced anything we had on the floor at that time. That was so much larger and so much more capable than we’d seen. So they passed an Act of Congress to sort of say, ‘We need to be more competitive in the supercomputing fields’ and tasked ASCR [DOE’s Advanced Scientific Computing Research program] in the Office of Science with creating a program and systems that could actually deliver large-scale science, and that really grew into the LCF’s [DOE’s leadership computing facilities] in 2006.

Scott: The leadership computing facilities, ALCF and OLCF, serve the portion of the open-science community that needs resources larger and more powerful than they could get anywhere else to pursue the most compelling and impactful research projects.

Katherine: This is very connected to what I just mentioned—because the ALCF and the OLCF [Oak Ridge Leadership Computing Facility], I’ll mention—this is referring generally to the LCFs. They are national user facilities, and that has a very specific meaning. When these two facilities were created, the premise was that they have to serve open science—so this is the stuff that will be published; it’s not going to be kept behind a fence, for example—and that anyone can compete. The entire research community who thinks that they have a problem that needs substantially larger resources than they could get any other place, can compete for time, regardless of funding source, regardless of location. It’s really open for anyone who might really have impactful work.

So as I mentioned, we’re also looking for those projects that are not only super impactful but where they could not do that work without maybe ten to a hundred times the resource they might get at another compute facility.  The primary way that people get access to deliver on that mission is through the INCITE program. This is a program that Oak Ridge and Argonne jointly manage. I happen to be the program manager for that. It’s a yearly call, for as I said, the most competitive, most compelling, most impactful projects that need the scale of resources that we build. But that’s really how we deliver on that mission because it’s agnostic to funding sources; it’s agnostic to field. It’s not tied to DOE mission at all. And they get about 60 percent of the time at both facilities. So that’s the primary way. There’s other mechanisms that people can get access.

ASCR itself runs an allocation program using 30 percent of the time on the systems, and that is a little bit more focused to DOE mission. That doesn’t necessarily mean that you need DOE funding, but it’s focused to priorities for the Department of Energy at that particular time. But then, given those two programs that everybody’s competing for, the thing that many people use to get started is the facilities have a discretionary program. And this is where you can apply, get really relatively rapid turnaround in getting an award. It tends to be small, but it allows you a chance to get onto the system and really get your feet wet. INCITE AND ALCC are competitive, and you have to be ready to use the system to really be successful in those competitions, and so that’s what the discretionary program is for. I’ll also point out INCITE is prepping for its 2024 call. We are going to announce that, fully all the details, in April, but information will continue to be uploaded as we go forward in the next couple of months. And that will be the call where we’ll be awarding Aurora, and obviously, Frontier was awarded for 2023 as well.

 

Link to listen and access a full transcript: https://www.exascaleproject.org/delivering-impactful-science-deploying-aurora-and-partnering-with-ecp-at-the-alcf.

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Source: Scott Gibson, Exascale Computing Project