Information on /tmp, /usr/tmp, /var/tmp, and /playpen directories
Reviewed by Bil Hays 5/2/14
This article describes the handling of the directories /tmp, /usr/tmp, /var/tmp, and /playpen on our systems. Computer Services has taken steps to make the handling consistent and to make the procedures followed with these directories known to users so there will be no surprises.
See also here for information on the large amount of playpen space available via AFS.
The purpose of the tmp directories is for very short-term local storage of files that are in active use and do not need to be backed up. The /playpen directories are for short-term storage of large files or directories that are in active use and do not require backups. For example, you might use this to download some public domain software source code, compile the software, move the binaries to a more permanent location, and then delete the source.
Nothing in /tmp, /usr/tmp, /var/tmp, and /playpen is ever backed up on our systems.
There are two kinds of playpen partition: public and private. Currently there are public NFS playpen partitions on the Linux servers bluetang, snapper, and classroom, as well as an AFS playpen space at /afs/unc/playpen. Anyone can write to these partitions, though you have to first have a directory created in /afs/unc/playpen. (See here for more info.) Private playpen partitions are are on private machines; they are writable by the owner of the machine and by others as specified by the owner.
None of the tmp or playpen partitions are cleaned up automatically.