Hi - could it be related to the problem described here by Robin Whalley:
https://forum.dxo.com/t/performance-problem-and-fix/13474
The problem he has been having seems to be related to DXO PL creating lots of new .dop files, for every image, following an update. It has happened with his Mac and Windows machines. Read his post for a possible solution to explore. Though others have not been able to duplicate the problem.
Nigel