SCALABLE AND PARALLEL GARBAGE COLLECTION METHOD AND SYSTEM FOR INCREMENTAL BACKUPS WITH DATA DE-DUPLICATION

摘要

In accordance with exemplary embodiments, a scalable and parallel garbage collection system for incremental backups with data de-duplication may be implemented with a memory and a processor. The memory may store a changed list at a current time, a before-image list including previous versions of the first overwrite at a current time for each of a plurality of overwritten physical blocks in said storage system, a garbage collection related change list and a recycle list. With these lists configured in the memory, the processor limits the garbage collection to incremental changes and distributes garbage collection tasks to a plurality of participating nodes. For garbage collection, each physical block may associate with an expiration time and a reference count. When the reference count drops to zero, the physical blocks are recycled based on the expiration time.