Hi Chris,
Whilst this isn't under the control of BaseX is there any advice of a newer version, or recommendations for handling connection pools.
For more information, you could try to contact Charles Foster [1]. An altenative could be to directly run your queries in BaseX (e.g. in the GUI), or e.g. use our REST interface [2] in order to see if you get better performance. Are you only retrieving documents, or are you also running queries?
Cheers, Christian