Revision deletion markers

• US 9,576,018 B2
• Filed: 08/01/2014
• Issued: 02/21/2017
• Est. Priority Date: 10/09/2007
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Resch, Jason K.
• Primary Examiner(s): Joo, Joshua
• Assistant Examiner(s): Naji, Younes
• Application Number:
  US14/449,487
• Publication Number:
  US 20140344394A1
• Time in Patent Office: 935 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1443 Transmit or communication errors
• CPC Class Codes: G06F 11/1474 in transactions G06F16/20 takes precedence
• CPC Class Codes: G06F 16/2365 Ensuring data consistency and integrity
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

A method begins by receiving a delete data object request within a dispersed storage network (DSN). The method continues by determining a set of dispersed storage (DS) units within the DSN that store a set of encoded data slices associated with the data object. The method continues by determining a revision number of the set of encoded data slices. The method continues by sending a delete marker and write command to the set of DS units for deletion of the data object. The method continues by receiving at least one receive write acknowledgement from at least some DS units of the set of DS units to produce the deletion. The method continues when a write threshold is met, by sending a commit command to the DS unit storage set and receiving commit acknowledgments from the DS units and sending a finalize command to the set of DS units to delete the data object.

Claims

1. A method comprises:

receiving a delete data object request to delete a data object within a dispersed storage network (DSN);

determining a set of dispersed storage (DS) units within the DSN that store a set of encoded data slices associated with the data object;

determining a revision number of the set of encoded data slices;

determining a delete marker based on one or more of information in the delete data object request, operational parameters, the set of DS units, a data object name, a source name, a slice name and the revision number;

sending the delete marker and a write command to the set of DS units for deletion of the data object;

receiving at least one receive write acknowledgement from at least some DS units of the set of DS units to produce the deletion;

when a number of the write acknowledgements received from the at least some DS units meets a write threshold, sending a commit command to the set of DS units and receiving commit acknowledgements from at least some DS units; and

when a number of the commit acknowledgements received from the at least some DS units meets the write threshold, sending a finalize command to the set of DS units to delete the data object.

2. The method of claim 1, wherein the delete data object request includes one or more of:

data object name;

revision number;

user ID;

priority indicator;

security indicator; and

performance indicator.

3. The method of claim 1, wherein the determining a set of DS units is based on one or more of:

a virtual DSN address to physical location table lookup;

a list;

a vault lookup;

a command;

a predetermination;

a message; and

the operational parameters.

4. The method of claim 1, wherein the determining the revision number is based on one or more of:

a received revision number;

a query to the set of DS units to determine the last revision number;

a command;

a message;

a predetermination; and

a list.

5. The method of claim 1, wherein the sending the delete marker and the write command is based on one or more of:

the delete marker specifying the revision number and setting up future deletions by one or more of the set of DS units.

6. The method of claim 1 further comprises the sending the commit command to include preventing deletion of a previous revision of the set of encoded data slices.

7. The method of claim 1 further comprises the sending the finalize command directing the set of DS units to point to a new revision as a current revision.

8. The method of claim 1 further comprises the sending the finalize command to include a deletion of a previous revision of the set of encoded data slices.

9. The method of claim 1 further comprises determining the finalize command is for deleting the marker and subsequently deleting the marker.

10. The method of claim 1, wherein the delete marker comprises encoding null data to produce encoded data slices based on the delete marker in accordance with the operational parameters.

11. A computing device of a dispersed storage network (DSN), the computing device comprises:

an interface;

memory; and

a processing module operably coupled to the interface and the memory, wherein the processing module is operable to;

receive, via the interface, a delete data object request to delete a data object within the dispersed storage network (DSN);

determine a set of dispersed storage (DS) units within the DSN that store a set of encoded data slices associated with the data object;

determine a revision number of the set of encoded data slices;

determine a delete marker based on one or more of information in the delete data object request, operational parameters, the set of DS units, a data object name, a source name, a slice name and the revision number;

send, via the interface, the delete marker and a write command to the set of DS units for deletion of the data object;

receive, via the interface, at least one receive write acknowledgement from at least some DS units of the set of DS units to produce the deletion;

when a number of the write acknowledgements received from the at least some DS units meets a write threshold, send, via the interface, a commit command to the set of DS units storage set and receiving commit acknowledgements from at least some the DS units; and

when a number of the commit acknowledgements received from the at least some DS units meets the write threshold, sending, via the interface, a finalize command to the set of DS units to delete the data object.

12. The computing device of claim 11, wherein the delete data object request received by the interface, includes one or more of:

data object name;

revision number;

user ID;

priority indicator;

security indicator; and

performance indicator.

13. The computing device of claim 11, wherein the processing module further functions to determine the set of DS units by one or more of:

a virtual DSN address to physical location table lookup;

a list;

a vault lookup;

a command;

a predetermination;

a message; and

the operational parameters.

14. The computing device of claim 11, wherein the processing module further functions to send, via the interface, the sending the delete marker and write command to include one or more of:

the delete marker specifying the revision number and setting up future deletions by one or more of the set of DS units.

15. The computing device of claim 11, wherein the processing module further functions to send, via the interface, the commit command to include preventing deletion of a previous revision of the set of encoded data slices.

16. The computing device of claim 11, wherein the processing module further configured functions to send, via the interface, the finalize command to direct the set of DS units to point to a new revision as a current revision.

17. The computing device of claim 11, wherein the processing module further functions to send, via the interface, the finalize command to include deletion of a previous revision of the set of encoded data slices.

18. The computing device of claim 11, wherein the processing module further functions to determine the finalize command for deleting the marker and subsequently deletes the marker.