Hello Largou,The link in the compatibility report are bare minimum. It all depend on the volume and the type of document you are processing.The key here is ensure that production required datacap to be in a distributed system. Follow the redbook for vertical or horizontal scaling.In 9.19 they introduce 64 bit action library which require a little more memory IMO.Since it's a VMware environment you can expand as needed.
Rulerunner rule of thumbs is one core per thread. You can add more thread to core provided cpu does not exceed 80%.I also recommend keeping your DB small since it's very chatty with the DB.https://www.ibm.com/support/pages/how-clean-out-large-volumes-old-and-stale-records-datacap-engine-database-tablesHope this helps.