Method and apparatus for reclaiming data storage volumes in a data storage library.

摘要

A procedure for the optimal processing of variable-cost actions such as encountered in the storage reclamation procedures for a multivolume data library (10). The procedure introduces a temporary processing queue to minimize idle processing capacity during the scanning and sorting of a large plurality of variable-cost actions such as the recycling of a plurality of data storage volumes each having a variable recycle processing cost related to the fraction of valid data remaining on the volume. Volumes (actions) are selected for the immediate queue according to a dynamically-adjusted threshold test for the processing cost. This processing cost threshold is dynamically adjusted to optimize the immediate queue in relation to the available processing capacity. After scanning and sorting all volumes according to recycle processing cost, the temporary (immediate) queue is updated to a final recycle processing queue by appending a sorted deferred queue to the remainder of the immediate queue. The procedure of this invention minimizes idle processing capacity during the queue-building interval, thereby optimizing the number of recovered data storage volumes released in a given time interval. <IMAGE>