Patent ID: 8762634
Filing Date: 2014-06-24
Classification: G06F

Abstract:
1. A method to efficiently restore data from a sequential-access backup archive, the method comprising: receiving a candidate list identifying data sets that are potentially contained within a backup archive configured to be accessed sequentially, the candidate list being provided in an environment where it is unknown which data sets are actually contained in the backup archive; receiving a filter list identifying data sets that are desired to be restored from the backup archive; generating, from the candidate list and the filter list, a search list identifying data sets that are to be ignored when searching the backup archive, wherein the search list is separate from the filter list; sequentially performing a plurality of searches in the backup archive such that the plurality of searches collectively performs a single pass through the backup archive, wherein a first search of the plurality of searches begins at a beginning of the backup archive, and each successive search of the plurality of searches begins from a last accessed portion of the backup archive, and each of the plurality of searches stops upon one of the following occurring: (1) encountering a data set not listed in the search list regardless of whether the data set is listed in the filter list, and (2) encountering an end of the backup archive; and upon encountering a data set not listed in the search list, restoring the data set if the data set is listed in the filter list.