ExCALIBUR at HPC/AI Days Durham

The University of Durham is a hotbed of HPC research and scientific computing, with the University involved in many ExCALIBUR projects. Building on the success of HPC/AI Days in 2023, this year saw the conference return once again the week before ISC. The idea of HPC/AI Days is that the event comprises an overarching agenda of HPC but with several different subthemes and focus topics throughout the week.

ExCALIBUR was central to the HPC/AI Days schedule this year, contributing thirty talks spread out over seven sessions, a tutorial, an evening focus session, and also posters. In addition to all this, we also had an ExCALIBUR booth with merchandise and information about the programme (including the now famous ExCALIBUR sword!) As many of the ExCALIBUR projects are now entering their final phase, this conference was a fantastic opportunity for the programme to share successes and outcomes both between projects and also outside of the programme, exploring where there might be fruitful collaborations and/or technology sharing.

The overarching theme of HPC/AI Days this year was around the multi-faceted challenges faced by HPC centres and their users. This was broken into three subtopics; challenges attracting and retaining talent, the fact that many codes suffer from a lack of scalability and efficiency (and notably that supercomputers consume a lot of energy which is increasingly becoming a challenge for many institutions with a strong push towards green or even Net-Zero computing), and thirdly the permanent tension between the ML/AI community and the traditional simulation customers. The thirty ExCALIBUR project talks, which were scheduled throughout the conference, explored these challenges from different angles, with the intention being for these to share experiences and discuss potential approaches and solutions across a wide range of application domains. The schedule illustrates the range of topics covered by these talks including, just to name a few; novel architectures such as RISC-V, domain specific languages and compilers for FPGAs, agent based modelling on HPC machines, challenges associated with benchmarking, quantum computing, RSE and training.

The conference began, on the Tuesday morning, with two tutorials. One of these was a tutorial on the Cerebras CS-2 machine delivered by the CGRA and PETSc on CS-2 ExCALIBUR H&ES projects. It was an opportunity for these teams to deliver the material (available here) which they have developed as part of their knowledge exchange activities during ExCALIBUR, with guest accounts provided for the CS-2 so attendees could run their codes on the actual 800,000 cores machine itself. We were fortunate to be joined by Leighton Wilson, who is an HPC Solutions Engineer at Cerebras, who not only delivered part of the tutorial, but was also on-hand to answer any especially tricky questions and advise attendees on how to best port their own codes to the CS-2. The other tutorial, which was run in parallel, was given by NVIDIA and introduced the new Grace Hopper architecture of which they have recently installed three nodes under the umbrella of the N8 system in Durham. This was therefore a great opportunity for people to gain access to Grace Hopper and experiment with the Durham system.

Whilst the Tuesday evening delivered glorious weather, with a fish and chips van providing a tasty supper thanks to DDN, attendees were kind enough to come inside en-mass for the ExCALIBUR-ECP focus session where we introduced and discussed the ExCALIBUR-ECP collaboration programme. This programme provides an opportunity to fund visits to and from the USA, driving collaboration between ExCALIBUR and ECP projects. A focus session at HPC/AI Days enabled us to gain feedback from the attendees around what sort of activities should be prioritised by the programme, advertise this opportunity to those attending, and also consider how to ensure that the programme delivers its intended impact.

A poster session and reception, fuelled by pizza, was held on the Wednesday evening and as part of this many ExCALIBUR projects displayed posters and were on hand to discuss the details of their work with attendees. This session was a great opportunity to drive further networking between ExCALIBUR projects and to those outside the programme, all in a relaxed atmosphere. There were also a lot of follow up discussions from the talks themselves, enabling participants to catch speakers and ask questions that they did not have an opportunity to raise in the session itself.

Whilst the focus of this article has been on the ExCALIBUR related activities at HPC/AI Days, there were many other activities that also went on and made the event the success it was. For example, six keynote talks were given by a range of world-leading experts that covered a plethora of topics, a conference reception speech was given on the Thursday evening which explored the current enthusiasm for AI/ML workloads through the lens of lessons learnt by the HPC community over many years. DiRAC and AI focus sessions, as well as the Lustre user group and a Women in HPC (WHPC) event considering community building and fostering diversity where also very popular. In addition to the technical programme and evening receptions, attendees also enjoyed a guided tour of the castle and, coupled with the fantastic weather throughout the week, it is fair to say that Durham really delivered for HPC Days this year.