Keynote: Designing High-Performance Storage for a World after Hard Drives

Glenn K. Lockwood

National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory

Abstract: We will discuss the architecture of the Perlmutter file system and the quantitative approach NERSC used to ensure that this all-flash file system would provide the best balance of capacity, performance, endurance, and stability for NERSC's 8,000 users. We will also discuss unresolved challenges in designing extreme-scale all-flash storage systems, then conclude with several promising future directions in storage systems design that NERSC will be pursuing over the next five years.

Bio: Glenn K. Lockwood is the principal storage architect at the National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory where he leads future storage systems design, I/O performance engineering, and many storage R&D activities across the center. He was a lead designer of the 35 PB all-NVMe Perlmutter file system, and he also played a key role in defining NERSC's Storage 2020 vision which culminated in the deployment of its 128 PB Community File System. In addition to storage systems design, Glenn is also actively engaged in the parallel I/O community; he represents NERSC on the HPSS Executive Committee, is a maintainer of the IOR and mdtest community benchmarks, and is a contributor to the Darshan I/O profiling library. Glenn holds a Ph.D. in materials science and a B.S. in ceramic engineering from Rutgers University.

Invited Talk: The Storage System of the Fugaku Supercomputer

Takuya Okamoto, Fujitsu Ltd.

Abstract: The Fugaku supercomputer is currently the world's fastest supercomputer, developed by RIKEN and Fujitsu. To provide a large-capacity and high-performance storage system, the Fugaku adopts 3-level hierarchical storage system: the 1st layer that serves as a dedicated high-performance filesystem for each job execution, the 2nd layer that provides large-capacity shared filesystems used by users and jobs, and the 3rd layer that provides commercial cloud storage. The 2nd layer storage adopts Fujitsu Exabyte File System (FEFS), a Lustre based filesystem developed during the K computer development. For the 1st layer storage, we have developed a new filesystem called Lightweight Layered IO-Accelerator (LLIO). LLIO provides 3 types of area to the jobs: a transparent cache of the 2nd layer filesystem, and 2 temporary filesystems. LLIO also provides an efficient file copying command to relieve hotspots which often lead to performance bottleneck when large scale jobs read shared input files. This talk presents an overview of the Fugaku storage system, LLIO functionalities, and their performance.

Bio: Takuya Okamoto received his B.E., M.E. degrees from The University of Tokyo in 2014, 2016, respectively. Afterwards he joined Fujitsu Ltd. He has spent 5 years as developer for Lightweight Layered IO-Accelerator (LLIO).

Invited Talk: Meaningful Measurements? IO500’s 5th Year’s Search for Meaning

Jay Lofstead, Sandia National Laboratories

Abstract: The IO500 was created as a way to encourage users to submit information about their data center, particularly, their storage systems, by providing a competition for bragging rights. The initial workloads were justified well at the time and the 10 Node Challenge was added to increase participation. With things seemingly moving along, reflection on the existing benchmarks and how to represent new workloads, and if they are relevant, has caused considerable discussion. This talk will examine the roots and motivations for the IO500 benchmark suite and what challenges have been revealed in meaningful measurements that are useful beyond a competition.

Bio: Dr. Jay Lofstead is a Principal Member of Technical Staff in the Scalable System Software department of the Center for Computing Research at Sandia National Laboratories in Albuquerque, NM. His work focuses on infrastructure to support all varieties of simulation, scientific, and engineering workflows with a strong emphasis on IO, middleware, storage, transactions, operating system features to support workflows, containers, software engineering and reproducibility. He is co-founder of the IO-500 storage list. He also works extensively to support various student mentoring and diversity programs at several venues each year including outreach to both high school and college students. Jay graduated with a BS, MS, and PhD in Computer Science from Georgia Institute of Technology and was a recipient of a 2013 R&D 100 award for his work on the ADIOS IO library.