Are you saying it's only 5GB or you only have 5GB space? I can't imagine a situation where you would only have 5GB available on disk.
If you only have 5GB total space... you really need to free some up.
That said, you can do the steps Adatole mentioned to limit how much data SW is collecting each day. You also could manually purge some of your historical data, but it's not something that I would recommend doing if you don't already know how.
