[Plugin: WordPress Flickr Manager] Database Cache too big

Hi!
I have some problems with the plugin.
The Database is getting too big because of the cache (40mb now of 55 total). But when i try to change the cache to file System i have some errors.

I need to clean the database. Is the file system worse than the database cache option?
How can i fix it?

Thanks.

https://www.ads-software.com/extend/plugins/wordpress-flickr-manager/