| # What is this directory? | |
| * In order to perform certain functions, spark sometimes needs to write temporary data to the disk. | |
| * Previously, a temporary directory provided by the operating system was used for this purpose. | |
| * However, this proved to be unreliable in some circumstances, so spark now stores temporary data here instead! | |
| spark will automatically cleanup the contents of this directory. | |
| (but if for some reason it doesn't, if the server is stopped, you can freely delete any files ending in .tmp) | |
| tl;dr: spark uses this folder to store some temporary data. | |