From the announcement email:
RapidCode - Objects upgraded to global, named locks for interprocess synchronization and safety.
What is the upshot of this? Is it going to cost more (time) for the OS-layer of RMP to do its locking when I call RapidCode API functions? What are the advantages and disadvantages?
The upshot is that if you have multiple processes reading SDO values (say, RapidSetup and your app), you’ll no longer get “busy” errors or incorrect values.
We were already using global locks for all internal objects (of which there are many) so this change impacts a relatively small number of objects. We looked closely at our method timing tests and the changes were negligible/unmeasurable.