High Performance Storage System (HPSS) is a flexible, scalable policy-based Hierarchical Storage Management product developed by IBM in collaboration with five DOE National Labs (LLNL, LANL, LBNL, ORNL, SNL). HPSS enables a user to use cluster, LAN, and/or SAN technology to aggregate the capacity and performance of many computers, disks, and tape drives into a single virtual file system.
The 6.2 and 7.1 releases of HPSS have full support on AIX and Linux. The HPSS data mover and client API are supported on AIX, Linux, IRIX, and Solaris.
HPSS supports a variety of methods for accessing and creating data. Among them are support for FTP, parallel FTP, VFS (Linux), as well as a robust client API with support for parallel I/O.
Two of the larger HPSS sites, LANL and LLNL had 13 and 11.7 Petabytes of data stored within a single HPSS instance and namespace as of October 13, 2008.
On November 14, 2007, the San Diego Supercomputer Center along with IBM, DataDirect, and Brocade demonstrated a "Billion File" test which successfully backed up a billion files from GPFS into HPSS.