-- After running many flow, the ended workflow actions remain which causes performance issues.

* Go to the XPM_params.properties files and in the "Purge auto parameters section,
set enable_purge_wfwaction to true

You can also set purge_xfxaction_delay which defines the interval between the end of a workflow action and its autmatic purge and purge_wfwaction_timeout which set the time that the system waits after the worflow action ended before deleting it.
All these values are in days