COPY AND FORWARD FOR A SIMULTANEOUSLY COPYING GARBAGE COLLECTION

摘要

A procedure is provided to optimize copying of a data object in a concurrent copying garbage collection operation. In one embodiment, a source copy of the data object that is to be copied as part of the garbage collection operation is recognized. Copying of the source copy to a target location is initiated by a primary accessing thread. This initiation of copying involves creating a temporary target header for the target at the target location that includes an indicator set to indicate that copying is in progress. While copying is taking place, any other accessing thread attempting to use the data object is stopped as long as the indicator indicates that copying is in progress. Once the copying is complete, the target object header is replaced with a copy of the source object header and the indicator is reset.