IBM General Parallel File System (GPFS) is a high performance parallel filesystem featuring storage virtualization, high availability and is designed to manage large amounts of file data, You can find out more about GPFS in this introduction.
By default all users of the atlas gpfs space get 100 GB in the u directory and 2 TB in the g dir.
On hosts running native gpfs like the rhel6-64 cluster you can issue the following 2 commands to see your quota and space used:
df -h /gpfs/slac/atlas/fs1/d/$USER
df -h /gpfs/slac/atlas/fs1/u/$USER
On other hosts that dont run the gpfs code, but do have nfs access, you can issue:
df -h /nfs/slac/atlas/fs1/d/$USER
df -h /nfs/slac/atlas/fs1/u/$USER
Below is a schematic of a typical SCS GPFS storage building block. It includes two file servers, two storage servers and two storage arrays. The two sets of servers operate as ACTIVE/ACTIVE, but also provide failover capability if needed. This example would provide 320 TB of space. Local iozone tests show max write ~4GB/sec, max read ~6GB/sec, using large block sequential I/O.