Pruning free blocks out of a decremental backup chain

Abstract

Pruning free blocks out of a decremental backup chain. In one example embodiment, a method for pruning free blocks out of a decremental backup in a decremental backup chain includes identifying a decremental backup chain, and pruning free blocks out of the target decremental backup.

1 . A method for pruning free blocks out of a decremental backup in a decremental backup chain, the method comprising:
 identifying, for pruning, a target decremental backup in the decremental backup chain; and   pruning free blocks out of the target decremental backup.   
     
     
         2 . The method of  claim 1 , wherein the pruning of the free blocks is performed in response to:
 a predetermined period of time, as set forth in a pruning policy, having passed since a most recent pruning of free blocks out of the target decremental backup.   
     
     
         3 . The method of  claim 1 , wherein the pruning of the free blocks is performed in response to:
 receiving input from a user that specifies the performance of the pruning of free blocks out of the target decremental backup.   
     
     
         4 . The method of  claim 1 , wherein the pruning of the free blocks is performed in response to:
 removing an oldest decremental backup from the decremental backup chain.   
     
     
         5 . The method of  claim 4 , wherein the removing of the oldest decremental backup from the decremental backup chain is performed in response to:
 a predetermined period of time, as set forth in a retention policy, having passed since a point in time represented by the oldest decremental backup;   a predetermined aggregate size limit, as set forth in the retention policy, having been reached for the decremental backup chain;   a predetermined number of backups limit, as set forth in the retention policy, having been reached for the decremental backup chain; or   some combination thereof.   
     
     
         6 . One or more non-transitory computer-readable media storing one or more programs that are configured, when executed, to cause one or more processors to perform the method as recited in  claim 1 . 
     
     
         7 . A method for pruning free blocks out of a base backup of a decremental backup chain, the method comprising:
 identifying the decremental backup chain that includes zero or more decremental backups of a source storage and the base backup of the source storage; and   pruning free blocks out of the base backup.   
     
     
         8 . The method of  claim 7 , wherein the pruning of the free blocks is performed in response to:
 reaching a predetermined point in time, as set forth in a pruning policy, for pruning of free blocks out of the base backup.   
     
     
         9 . The method of  claim 7 , wherein the pruning of the free blocks is performed in response to:
 receiving input from a user that specifies the performance of the pruning of free blocks out of the base backup during a particular period of time.   
     
     
         10 . The method of  claim 7 , wherein the pruning of the free blocks is performed in response to:
 removing one or more oldest decremental backups from the decremental backup chain.   
     
     
         11 . The method of  claim 10 , wherein the removing of the one or more oldest decremental backups from the decremental backup chain is performed in response to:
 a predetermined period of time, as set forth in a retention policy, having passed since a point in time represented by the newest backup of the one or more oldest decremental backups;   a predetermined aggregate size limit, as set forth in the retention policy, having been reached for the decremental backup chain;   a predetermined number of backups limit, as set forth in the retention policy, having been reached for the decremental backup chain; or   some combination thereof.   
     
     
         12 . One or more non-transitory computer-readable media storing one or more programs that are configured, when executed, to cause one or more processors to perform the method as recited in  claim 7 .