see the reports folder is massive, it doesn't seem to purge reports after it's sent them via email.
I think that was fixed somewhere in the 2.7 series.
I'm not quite sure how to tell which database it's using,
Your last image reveals it to be the H2 database (so you have a Mango/databases/mah2.h2.db file, I would guess). This means you shouldn't have to worry about a database conversion before doing the upgrade.
That's SQL I think?
It is. Derby, H2, and MySQL are all SQL databases.
I'll give it a go, I've copied the whole folder sideways,
Sounds good. If that doesn't solve the issue, it could be caused by a few other things like,
- A meta point with multiple points from the same data source updating context. This used to drive CPU usage up quite far.
- An infinite event loop --> point A generates an event for B, B for A, etc. (less likely in 2.4 since fewer things had context update options)
- The events table is large.
I'm not sure if that 2GB size reflects the NoSQL, the H2, or both, but you may also see performance improvements by doing a restore, via: create a backup from the SQL backup configuration section of the system settings page, stopping Mango, moving the Mango/databases/mah2.h2.db file for safe keeping, starting Mango and doing a restore. This should shrink your H2 database substantially, which should accelerate everything some. We can investigate that if necessary.