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Today's scientific research involves increasingly large volumes of increasingly complex data. At the same time, CPU performance has improved well beyond storage media, which can create bottlenecks in HPC environments. Read this section to learn how to optimize your storage usage and improve I/O performance on Palmetto.

Palmetto provides three data spaces: home, scratch, and group project storage.

Every user has a home directory and access to the scratch file systems. Group project storage is allocated for faculty to house their data and can only be accessed by users having the owner’s approval. Each data space is accessible from anywhere in the cluster.

Storage Hardware Grid

The table below describes each file system on Palmetto and the hardware for the storage medium and connection to the nodes.

NameSizeDisk TypeFile SystemConnection TypeBackup
/home250GB per userSSDIndigoNetwork (IB, ethernet) yes
/scratch5 TB per userSSDIndigoNetwork (IB, ethernet) no
/local_scratch99GB - 2.7TB per nodeHDD, SSD, NVMeext4Internal (SAS, SATA, PCIe) no
/project/{path}Varies by ownerSSDIndigoNetwork (IB, ethernet) yes
What do the abbreviations in the storage hardware grid mean?

The legend below can be used to understand the abbreviations in the storage hardware grid table.

HDDHard Disk Drive
SSDSolid State Drive
NVMeNon-Volatile Memory Express
PCIePCI Express
PCIPeripheral Component Interconnect
SASSerial Attached SCSI
SCSISmall Computer System Interface
ATAAdvanced Technology Attachment

Performance Guidelines

Generally speaking, /local_scratch will always be the fastest file system to use because there is no network involved. However, this space cannot be shared between a group of nodes participating in a job, and the data must be moved to permanent storage before the job completes.

/scratch is our newest parallel file system that runs atop flash storage. It performs well across most access patterns.

The RCDE team encourages you to test your workflows against all three file systems to see which one works best for you.