Usage Charging at NERSC

Charged Resources

At NERSC two resources are associated with usage charging:

1. MPP resources: There are four "Massiveley Parallel Processing" resources for the current Allocation Year:
   • Cray XT4, Franklin
   • IBM POWER 5, Bassi
   • LNXI Opteron Cluster, Jacquard
   • SGI Altix, DaVinci
   Charges for these MPP resources all accrue to the user's MPP repository. The charge unit is the MPP hour, which is currently defined as equivalent to an SP Power3 hour. Please note that starting in allocation year 2009, the MPP hour will be equivalent to a Cray XT4 hour. Each MPP machine is charged at a different rate. See MPP Accounts and Charging.
2. HPSS resources: The charge unit for the HPSS Mass Storage system is the Storage Resource Unit (SRU). Three measures of use are included in computing SRUs:
   • GB of I/O transferred in and out of the system
   • GB of space used in the archive
   • number of files stored
   See HPSS Charging. A SRU calculator is available for estimating SRU usage.

Repositories

Allocations of NERSC computer time and archival storage are awarded by DOE to research groups. The allocations are awarded into project accounts, called repositories or repos.

Usage Reports

Usage for MPP and HPSS resources are collected and displayed by the NERSC Information Management system, NIM. The two most commonly used usage reports in NIM are:

• My Account Usage: This is the default display when you first log into NIM. It shows your personal usage by repository.
• Repository Usage: To see repository usage, type the repo name into the Repository box in the NIM main menu, then click Go.

There is also an inquiry-only command called getnim available on the computational (MPP) systems. Users can use getnim interactively and in scripts to get their account balances.