MAINTAINING REFERENCES TO RELATED OBJECTS IN A DISTRIBUTED STORAGE NETWORK

1 . A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method comprises:

receiving a delete snapshot request;

identifying a first directory file associated with the delete snapshot request;

accessing a first directory file entry associated with the delete snapshot request, wherein the first directory file entry corresponds to the first directory;

determining whether a second directory file is indicated for a source name reference associated with the delete snapshot request;

when the second directory file is indicated for the source name reference associated with the delete snapshot request, accessing the second directory file;

accessing a second directory file entry, wherein the second directory file entry corresponds to the second directory file, and further wherein second directory file entry is associated with the source name reference;

removing the source name reference from the second directory file ;

determining whether a snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry; and

when the snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry, deleting a data file corresponding to the delete snapshot request.

2 . The method of claim 1 , further comprises:

when the snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry, further deleting the first directory file entry; and

deleting a segment allocation table (SAT) associated with the delete snapshot request.

3 . The method of claim 2 , wherein the deleting the SAT associated with the delete snapshot request further comprises:

outputting one or more delete encoded slice messages to DSN memory, wherein the one or more delete encoded slice messages are associated with the SAT; and

deleting one or more sets of encoded slices corresponding to the SAT.

4 . The method of claim 2 , wherein the deleting the first directory file entry comprises:

producing a modified first directory file;

dispersed storage error encoding the modified first directory file to produce at least one set of encoded modified first directory slices;

and outputting the at least one set of encoded modified first directory slices to memory associated with the DSN.

5 . The method of claim 1 , further comprises:

when the snapshot corresponding to the delete snapshot request is not the most recent snapshot available for the first directory file entry, deleting the first directory file entry; and

deleting a segment allocation table (SAT) associated with the delete snapshot request.

6 . The method of claim 5 , wherein the deleting the SAT associated with the delete snapshot request further comprises:

outputting one or more delete encoded slice messages to DSN memory, wherein the one or more delete encoded slice messages are associated with the SAT; and

deleting one or more sets of encoded slices corresponding to the SAT.

7 . The method of claim 5 , wherein the deleting the first directory file entry comprises:

producing a modified first directory file;

dispersed storage error encoding the modified first directory file to produce at least one set of encoded modified first directory slices;

and outputting the at least one set of encoded modified first directory slices to memory associated with the DSN.

8 . The method of claim 1 , wherein the delete snapshot request includes at least one of a snapshot identifier (ID), a file name, a first directory source name, and a vault ID.

9 . The method of claim 1 , wherein the accessing a first directory file entry associated with the delete snapshot request includes at least one of:

obtaining a source name corresponding to the first directory file;

retrieving one or more sets of dispersed storage encoded slices associated with the first directory file from DSN memory;

dispersed storage error decoding the one or more sets of dispersed storage encoded slices associated with the first directory file to produce the first directory file;

identifying an entry of the first directory file corresponding to a snapshot identifier, wherein the snapshot identifier corresponds to the delete snapshot request; and

extracting the first directory file entry.

10 . The method of claim 1 , wherein the determining whether a second directory is indicated for a source name reference associated with the delete snapshot request further comprises:

accessing a linked directory source names field corresponding to the first directory file entry.

11 . The method of claim 1 , wherein the determining whether a snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry is based on extracting a snapshot identifier from a snapshot associated with the second directory file and comparing it to a snapshot identifier from a snapshot associated with the first directory file.

12 . The method of claim 1 , wherein the deleting a data file corresponding to the delete snapshot request comprises:

extracting a source name of the data file from first directory file entry;

outputting one or more delete encoded data slice messages to DSN memory; and

deleting the data file and a snapshot identifier associated with the delete snapshot request from DSN memory.

13 . A dispersed storage (DS) processing unit comprises:

a first module, when operable within a computing device, that causes the computing device to:

receive a delete snapshot request;

identify a first directory file associated with the delete snapshot request;

access a first directory file entry associated with the delete snapshot request, wherein the first directory file entry corresponds to the first directory; and

determine whether a second directory file is indicated for a source name reference associated with the delete snapshot request;

a second module, when operable within a computing device, that causes the computing device to:

when the second directory file is indicated for the source name reference associated with the delete snapshot request, access the second directory file;

access a second directory file entry, wherein the second directory file entry corresponds to the second directory file, and further wherein second directory file entry is associated with the source name reference;

remove the source name reference from the second directory file;

determine whether a snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry; and

when the snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry, delete a data file corresponding to the delete snapshot request.

14 . The DS processing unit of claim 13 , wherein the second module further causes the computing device to:

when the snapshot corresponding to the delete snapshot request is the most recent snapshot available for the first directory file entry, delete the first directory file entry; and

delete a segment allocation table (SAT) associated with the delete snapshot request.

15 . The DS processing unit of claim 14 , wherein the second module further causes the computing device to:

output one or more delete encoded slice messages to DSN memory, wherein the one or more delete encoded slice messages are associated with the SAT; and

delete one or more sets of encoded slices corresponding to the SAT.

16 . The DS processing unit of claim 13 , wherein the second module further causes the computing device to:

when the snapshot corresponding to the delete snapshot request is not the most recent snapshot available for the first directory file entry, delete the first directory file entry; and

delete a segment allocation table (SAT) associated with the delete snapshot request.

17 . The DS processing unit of claim 16 , wherein the second module further causes the computing device to:

output one or more delete encoded slice messages to DSN memory, wherein the one or more delete encoded slice messages are associated with the SAT; and

delete one or more sets of encoded slices corresponding to the SAT.

18 . The DS processing unit of claim 13 , wherein the delete snapshot request includes at least one of a snapshot identifier (ID), a file name, a first directory source name, and a vault ID.