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Custom File Attributes, or user attributes, can be used when more granular control is required than can be achieved using the standard file attributes options. Those options include File Name, Path, File Type, File Size, Modified Time, Create Time, Metadata Change Time, and Access Time. User Attributes use key value pairs to tag files with additional identifying criteria that SmartPools can then use to apply file pool policies. You can set file attributes by running the setextattr command.
Custom File Attributes are most often used to designate ownership or create project affinities. Consider a biosciences user expecting to access many genomic sequencing files when personnel arrive at the lab in the morning. That user might employ Custom File Attributes to ensure that the files are migrated to the fastest available storage.
Once Custom File Attributes are set, SmartPools uses them to specify location, protection, and performance access for a matching group of files. SmartPools uses Custom File Attributes exactly as File Name, File Type, or any other file attributes are used. Unlike other SmartPools file pool policies, Custom File Attributes can be set from the command line or platform API.