ALLOCATION OF ABSENT DATA WITHIN FILESYSTEMS

摘要

Systems and methods which provide an absent allocation technique with respect to absent data of a data structure for which data migration in a time-displaced data migration operation has not completed are disclosed. Through use of absent allocated data block states of an absent allocation technique of embodiments, dependency between source and destination data stores may be broken. An absent allocated data block state of embodiments stored within the data structure provides a suggestive indication that data of a data block of a data structure is absent from the data structure. A corresponding absent allocated data block state of embodiments stored external to the data structure provides a determinative indication that the data of the data block of the data structure is absent from the data structure. The absent data block determinative indictor of embodiments is updated as data continues to be migrated.