Patent ID: 8862639
Filing Date: 2014-10-14
Classification: G06F

Abstract:
1. A method of locking allocated data space, comprising: providing continuous data protection for a protected entity over a window of continuous data protection, where the protected entity as it was at any state during the window of continuous data protection is able to be accessed if desired with write-by-write granularity, including by: receiving, at a processor, an indication that selected previous version data associated with one or more selected copies of writes stored in the allocated data space are required to be retained; using the processor to store in a locked list, for each of those one or more metadata records corresponding to the one or more selected copies of writes, an identifier that identifies the metadata record as one associated with a copy of a write that is to be retained; and determining whether some allocated data space under consideration is available for reclamation based at least in part on (1) whether there is a stored identifier in the locked list and (2) the window of continuous data protection, wherein it is determined to not reclaim for reuse any storage location associated with a metadata record for which the corresponding identifier has been stored in the locked list.