Rockfish Hardware Summary

The Rockfish cluster is a high-performance computing (HPC) system operated by ARCH at Johns Hopkins University. As of 2025, Rockfish consists of:

  • 45,072 CPU cores across 841 nodes

  • Theoretical peak performance: 3.3 PFLOPs

  • Rmax: 2.1 PFLOPs (measured)

  • Parallel file systems: 3 IBM GPFS systems totaling ~13 PB of usable space

  • Network fabric: Mellanox HDR100 (1:1.5 topology)

  • Top500 Ranking: #443 as of November 2023

The following table summarizes the current node types available in the Rockfish cluster:

Type

Count

CPU

GPU

RAM

Storage

Total Cores

Compute

720

Intel Xeon Gold 6248R (Cascade Lake)

N/A

192 GB DDR4 2933MHz

1 TB NVMe SSD

36,864

Compute (Next-Gen)

46

Intel Xeon Gold 6448Y (Sapphire Rapids)

N/A

256 GB DDR5 4800MHz

2 TB NVMe SSD

2,944

Large Memory

25

Intel Xeon Gold 6248R (Cascade Lake)

N/A

1.5 TB DDR4 2933MHz

1 TB NVMe SSD

1,200

GPU (A100 40GB)

18

Intel Xeon Gold 6248R (Cascade Lake)

4 × NVIDIA A100 40GB

192 GB DDR4 2933MHz

1 TB NVMe SSD

864

GPU (A100 80GB)

10

Intel Xeon Gold 6338 (Icy Lake)

4 × NVIDIA A100 80GB

256 GB DDR4 3200MHz

1.6 TB NVMe SSD

640

GPU (L40S)

4

Intel Xeon Gold 6338

8 × NVIDIA L40S 48GB

512 GB DDR4 3200MHz

3.5 TB NVMe SSD

256

Fast Compute (Emerald Rapids)

18

Intel Xeon Gold / Platinum 8592+

N/A

512 GB TruDDR5 5600MHz

1.8 TB NVMe SSD

2,304

Note

Node specifications may change as new hardware is integrated into the cluster.

Total system core count: 45,072 cores across 841 nodes