A garbage collection process performs garbage collection operations in an object-based memory system associated with a processing environment. The garbage collection process receives, at a first garbage collection unit, object references derived from root data from a processor associated with the first garbage collection unit. In addition, the garbage collection process processes, at the first garbage collection unit, the root data received from the processor associated with the first garbage collection unit. The garbage collection process also determines which object references derived from the root data are associated with a second garbage collection unit. Upon determining that an object reference is associated with a second garbage collection unit, the garbage collection process communicates information representative of the object reference to the second garbage collection unit associated with the object reference.