27 August 2021

Durham University’s Ogden Centre for Fundamental Physics houses the ICC and DiRAC

A supercomputing facility at Durham University is using two Spectra tape libraries to store cosmological data about galactic evolution.

DiRAC (Distributed Research using Advanced Computing) is a federated facility, funded by the UK’s Science and Technologies Facilities Council (STFC).

It spans four sites at Cambridge, Durham, Edinburgh and Leicester. Durham houses the DiRAC Memory Intensive Service in its Institute for Computational Cosmology.

This high-performance computing system is used for theoretical modeling and HPC-based research in particle physics, astronomy and cosmology, and nuclear physics. The Durham HPC cluster has 812 nodes, 58,700 compute cores, and 230TB of DRAM backed up with 10PB of primary storage. It uses the GPFS and Lustre parallel file systems.

“Collaboration is key at DiRAC sites and we expect it from our technology providers,” said Alastair Basden, technical lead for the DiRAC Memory Intensive Service, Durham University. “We have seen Spectra step up to the mark more than once since the deployment of our Spectra T950 Tape Libraries. We’ve received very good support and advice from the Spectra team at every step of the way.”

Moreover, it is anticipated that DiRAC will generate 20PB of stored data by 2022. The data chronicles galactic formation and evolution and will need to be accessible for 15 years. DiRAC staff are using one Spectra T950 tape library to store this data, with a second T950 purchased as part of a general DiRAC phase-3 upgrade.
Both have four LTO-8 drives and media and data is accessed using the LTFS protocol. Atempo’s Miria software is the chosen data mover, managing both backup and archive processes from the primary storage.

The LTFS (Linear Tape File System) presents a tape drive that writes files sequentially as if it were a disk-based file:folder device, with files listed for random and not sequential access. There is an index (directory) stored on a tape cartridge which lists the cartridge’s contents as if they were in a file:folder structure. LTFS software in a server accessing a tape library reads a cartridge’s index and presents it in a file:folder format on screen.

The T950 scales from 50 to 10,250 LTO slots, with loading via ten-cartridge TeraPack trays, and has up to 120 tape drives.