ContactMechWorker.get[Entity]ContactMechValueMaps are old historic functions that resolve all contact mech context related to an Entity (Party, Facility, Order, WorkEffort).
The problem that they create too many db call during their execution that decrease OFBiz performance when the contactMech history grow.
On customer site I realized a new adaptation (oriented and not generic at all) and control the performance issue with a unit test :
The partyId "10375" is linked with more tha 600 contactMechs on my local site db. And the test excecution give :
total ~100s for ContactMechWorker and ~1.5s for CustomPartyWorker
Difference come that CustomPartyWorker works on a view entity gathering the data and populating GenericValue with makeValue (using the data within the view) instead of creating new getRelated db access.
I will implement this idea on generic context to improve these functions