File Storage Guidelines

Files can be stored in two places at PSC: in the Andrew File System (AFS), or in the File ARchiver (FAR). Each has advantages and disadvantages. You can minimize the time to retrieve a file by choosing the best place to store it based on factors such as filesize and frequency of use.

Retrieval is generally quicker from AFS, but you have limited space. Although you can request more AFS space by contacting User Services, you must justify the need.

FAR offers unlimited storage space, but it can take longer to get a file when it is needed. Each of your far files can be as large as 6 gigabytes.

Files which are small or used frequently should be stored in AFS. Any file smaller than about 150KB will be retrieved faster from AFS than from FAR.

Files larger than 150 KB should be archived on FAR. In addition, small files that are used infrequently can be efficiently stored on FAR if they are tar'ed into a larger file. Tarring smaller files to form a file of at least 50 MB and then storing it on FAR is best for performance.

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