GIMP uses several directories to store such things as add-on filters (plug-ins), scripts, brushes, etc., but also its swap and temporary files.
The top view in Directories controls Temp Dir and Swap Dir. The Swap Dir is, by default, in your personal GIMP directory located in your home directory. Often your home directory is on an NFS (UNIX) or SMB Windows™ server. If it is, GIMP will have its memory swap slowed down due to network latency. It is therefore very important that the GIMP directory is a local directory such as /tmp under Unix or C:\temp under Windows™. The temp dir is a directory where GIMP will store temporary files such as palettes that you work with. The temp dir should not be in a public directory such as /tmp, but a directory to which only you have read and write access.
The subcategories such as Brushes, Patterns, and Plug-Ins controls where GIMP will search for those items and in which order.
Mark it by clicking on it. Type the changed path or browse the files system with the ... browse button. Press Enter to activate the new path.
Mark a search path and click on the or buttons to change the search order.
Click on the button. Type the path or browse the files system with the ... browse button. Press Enter to activate the path.
Mark the path you wish to delete and click on the icon.