Towards Next JCAHPC System: Oakforest-PACS II

Oakforest-PACS system (OFP) was the first supercomputer system designed, installed, and operated by the Joint Center for Advanced High-Performance Computing (JCAHPC) under the collaboration between the Center for Computational Sciences at University of Tsukuba and the Information Technology Center at the University of Tokyo. OFP has contributed significantly to the development of computational sciences in Japan. Especially after the K computer was decommissioned in August 2019, OFP continued to provide large amounts of computing resources and successfully retired on Mar. 2022.
Now we plan to introduce the “Oakforest-PACS II” system (OFP-II) as the successor system to OFP in FY2024 with a peak performance of 200 PFLOPS. OFP-II consists of two groups of compute nodes, GPU accelerated nodes and CPU only nodes.
The design considerations for OFP-II architecture and the porting efforts for the existing applications to the GPU system will be presented and discussed.