EZproxy v7.1 introduced use of a SQLite database supporting the security rules and pseudonymous identifier features. When those databases are cleaned per your configuration settings, EZproxy uses temporary space on your system, defaulting to the /tmp directory. If you need to use temporary space in different filesystem, you may use the SQLiteTempDir directive to specify that location.
On Linux systems, the default path is /var/tmp.
On Windows systems, the default path is C:\temp.
SQLiteTempDir /path/to/directory