Object copying with re-copying concurrently written objects

摘要

Objects are copied concurrently with mutator execution, while tracking writes to the objects being copied. Objects (or fields) that are written into during copying are re-copied to the same destination locations. Mutators use the original objects until copying is complete and are, in some embodiments, atomically (with respect to the mutators) switched to use the new copies, together with a final re-copy.